Re: [QE-users] HP.x does not produce Chi files if computing Q-points separately

[Matteo Cococcioni]

Dear Chris,

before calling hp.x with compute_hp = .true., you have to run it with
sum_pertq = .true.. This step is exactly what allows the code to build the
chis from summing over the response at specific q-points.
Here is the excerpt from INPUT_HP:

sum_pertq LOGICAL
*Default:* .false.
*See:* start_q <https://www.quantum-espresso.org/Doc/INPUT_HP.html#start_q>,
last_q <https://www.quantum-espresso.org/Doc/INPUT_HP.html#last_q>,
perturb_only_atom
<https://www.quantum-espresso.org/Doc/INPUT_HP.html#perturb_only_atom>

If it is set to .true. then the HP code will collect
pieces of the response occupation matrices for all
q points. This variable should be used only whenstart_q
<https://www.quantum-espresso.org/Doc/INPUT_HP.html#start_q>, last_q
<https://www.quantum-espresso.org/Doc/INPUT_HP.html#last_q> and
perturb_only_atom
<https://www.quantum-espresso.org/Doc/INPUT_HP.html#perturb_only_atom>
are used.



Matteo



Il giorno gio 13 giu 2024 alle ore 23:08 O'Brien, Christopher John via
users  ha scritto:

> QE Users & Devs,
>
> I am attempting to use the linear-response calculation of U values (hp.x).
> This operation can take a lot of time, so much that my job times out before
> it finished. I’ve attempted to divide the job into q-points using the
> `start_q` and `last_q` options.
>
>
>
> However, when I do this, I will not get `chi` files when I attempt to
> calculate the linear response U value for any range of q-points using the
> input:
>
>
>
> &inputhp
>
> prefix="test",
>
> outdir="./",
>
> nq1 = 3,
>
> nq2 = 3,
>
> nq3 = 3,
>
> start_q = 11,
>
> last_q = 14,
>
> !find_atpert = 2,
>
> perturb_only_atom(2) = .TRUE.
>
> thresh_init = 0.01,
>
> alpha_mix = 0.1,
>
> conv_thr_chi=5.0e-6,
>
> iverbosity = 2,
>
> compute_hp = .FALSE.
>
> /
>
>
>
> In my HP folder I only see “test.dns.pert_1.q_11.dat” and “test.hub*” and
> “test.mixd*” files.
>
>
>
> After completing all of the qpoint calculations and attempting to run HP.x
> with `compute_hp=.TRUE.` the code informs me that I’m missing “chi” files.
>
>
>
> What am I missing to get this to work?
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
>


-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Using self-consistent occupation matrices in DFT+U

[Matteo Cococcioni]

Dear Mahmoud,

occupation='from_input' refers to the occupation of the Kohn-Sham states,
not to the occupation matrices of the Hubbard part.
As far as I know there is no flag to read those matrices only. However the
code reads them when you restart a DFT+U calculation from an existing
charge density. so I would try instead to set startingpot = 'file'.

Best,

Matteo

Il giorno dom 8 gen 2023 alle ore 16:24 Mpayami via users <
users@lists.quantum-espresso.org> ha scritto:

> Dear All,
>
> I pose the question of my last post in another way:
> In a DFT+U scheme, I do a vc-relax calculation with an input in which I
> had set the values for starting_ns_eigenvalue().
> In a certain case, the last scf on top of BFGS optimization gives
> reasonable results. Sometime ago Dr Iurii Timrov pointed out that the last
> scf uses the self-consistent occupation matrices resulted from last step of
> BFGS optimization.
> Now I would like to repeat the last scf manually, what the code
> automatically executes. To this end, I use ibrav=0, and insert the
> CELL_PARAMETERS as well as the ATOMIC_POSITIONS form the "final
> coordinates" in vc-relax. In addition, for the "occupation" I specify
> occupations='from_input' as stated in the DOC. Unfortunately, I get
> SEGMENTATION FAULT error.
> Could anybody please help to manage this issue?
>
> Best regards,
> Mahmoud Payami
>
> NSTRI, AEOI, IRAN
> mpay...@aeoi.org.ir
>
>
> - Original Message -
> --
> From: Mpayami via users (users@lists.quantum-espresso.org)
> Date: 18/10/1401 16:58
> To: Quantum ESPRESSO users Forum (users@lists.quantum-espresso.org)
> Cc: mahmoud.pay...@gmail.com
> Subject: [QE-users] disordered values for "starting_ns_eigenvalue(m,
> ispin, itype)"
>
> Dear All,
>
> I am using QE-7.1. In a DFT+U calculation, when I specify the values for
> "starting_ns_eigenvelue(m,ispin,itype)" in a certain order, then in the scf
> cycle, after iteration #1, the WARNING !!! appears that warns about
> modification according to specified starting_ns_eigenvalue().
> But the order of the modified eigenvalues are not the same as the ones
> specified in the input. Their magnetic quantum numbers "m" are changed.
> Is there any bug with this issue?
> Any comments is highly appreciated.
>
> Best,
> Mahmoud Payami
>
> NSTRI, AEOI, IRAN
> mpay...@aeoi.org.ir
> --
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] using occupation matricx in DFT+U

[Matteo Cococcioni]

Dear Mahmoud

the occupations are written on disk at the end of the self-consistent cycle
of a DFT+U calculation (you need a finite U at least).
if you restart a DFT+U calculation from a previous one, reading the
potential that was saved,
the code will automatically read also the occupations. I don't think you
can read only the occupations at the moment, although it would not be hard
to implement.

Best regards,

Matteo



Il giorno mar 13 dic 2022 alle ore 09:56 Mahmoud Payami Shabestari via
users  ha scritto:

> Dear All,
>
> Hi.
> For starting an scf run in DFT+U, how can I input the selfconsistent
> occupation matrix of a previous run? That is, how can I save a
> selfconsistent occupation matrix in a first run, and how can I input that
> to a second scf run?
> Any comments is highly appreciated.
>
> Best regards,
> Mahmoud Payami
>
> NSTRI, AEOI, Tehran, Iran
> Email: mpay...@aeoi.org.ir
> Phone: +98 (0)21 82066504
> 
>
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] LDA+U with Spin Orbit coupling in VC-RELAX. Are forces computed?

[Matteo Cococcioni]

Dear James,

as the error message says forces are not implemented with lda_plus_u_kind =
1.
perform the relaxation using lda_plus_u_kind = 0 (switching off spin-orbit)
and then you use ldau_kind = 1 on the relaxed structure. Hopefully
spin-orbit does not give a large contribution to forces and stresses, so
your equilibrium structure will be a reasonable one.

HTH,

Matteo



Il giorno mer 9 nov 2022 alle ore 17:47 Sifuna James 
ha scritto:

> Dear ALL,
>
> How do I go about this?
> I am having the flags below and I am performing a relaxation on monoclinic
> SrIrO3:
>
>
>
> *lda_plus_u=.true.  lda_plus_u_kind=1,Hubbard_U(1)=3.0  noncolin = .true.
> lspinorb = .true.*
> Unfortunately, the code is not happy. I am using versing 6.4.1 of the
> code.
> Below is the error
>
> *Error in routine force_hub (1):  forces in full LDA+U scheme are not
> yet implemented*
>
> Any help? Is there a way I can compute forces in Quantum espresso when
> Spin Orbit & LDA+U are both activated?
>
> James Sifuna
> The Technical University of Kenya
> J.
>
>
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] compiling QE with Ubuntu 22.04

[Matteo Cococcioni]

Dear users,

apparently the intel oneapi c compiler icc does not like Ubuntu 22.04
and/or viceversa and there is some incompatibility between the two which
I was not able to solve.
Following Prof. Giannozzi's advice I manage to compile after switching icc
--> gcc. I haven't tested the code yet, but I hope it works normally.

Matteo


Il giorno ven 7 ott 2022 alle ore 10:02 Matteo Cococcioni <
matteo.cococci...@unipv.it> ha scritto:

> Dera Chris,
>
> thanks for your advice. Unfortunately it does not work for me, not even
> upgradig git (which I didn't use anyway).
> My LD_LIBRARY_PATH seems to contain only oneapi locations.
> My problems seems related to /usr/include/stdio.h and
> /usr/include/stdlib.h:
>
> In file included from copy.c(3):
> /usr/include/stdio.h(830): error: attribute "__malloc__" does not take
> arguments
> __attribute_malloc__ __attr_dealloc (pclose, 1) __wur;
>  ^
>
> In file included from copy.c(4):
> /usr/include/stdlib.h(566): error: attribute "__malloc__" does not take
> arguments
>   __attr_dealloc_free;
>   ^
> Thanks,
>
> Matteo
>
>
>
> Il giorno ven 7 ott 2022 alle ore 07:26 Christoph Wolf
>  ha scritto:
>
>> Dear Matteo,
>>
>> I just tested with 22.04 and intel one API and the gitlab version with a
>> simple  ./configure --prefix=... worked without issues. On an older machine
>> I had some obscure error related to git, which was simply solved by
>> updating git.
>>
>> check if your LD_LIBRARY_PATH is properly set; I had some issues with
>> oneAPI not overwriting an older library location (no clue why).
>>
>> HTH!
>> Chris
>>
>> --
>> Group Leader "Theory of Quantum Systems at Surfaces"
>> IBS Center for Quantum Nanoscience
>> Seoul, South Korea
>>
>> ___
>> The Quantum ESPRESSO community stands by the Ukrainian
>> people and expresses its concerns about the devastating
>> effects that the Russian military offensive has on their
>> country and on the free and peaceful scientific, cultural,
>> and economic cooperation amongst peoples
>> ___
>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>> users mailing list users@lists.quantum-espresso.org
>> https://lists.quantum-espresso.org/mailman/listinfo/users
>
>
>
> --
> Matteo Cococcioni
> Department of Physics
> University of Pavia
> Via Bassi 6, I-27100 Pavia, Italy
> tel +39-0382-987485
> e-mail matteo.cococci...@unipv.it
>


-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] compiling QE with Ubuntu 22.04

[Matteo Cococcioni]

Dera Chris,

thanks for your advice. Unfortunately it does not work for me, not even
upgradig git (which I didn't use anyway).
My LD_LIBRARY_PATH seems to contain only oneapi locations.
My problems seems related to /usr/include/stdio.h and /usr/include/stdlib.h:

In file included from copy.c(3):
/usr/include/stdio.h(830): error: attribute "__malloc__" does not take
arguments
__attribute_malloc__ __attr_dealloc (pclose, 1) __wur;
 ^

In file included from copy.c(4):
/usr/include/stdlib.h(566): error: attribute "__malloc__" does not take
arguments
  __attr_dealloc_free;
  ^
Thanks,

Matteo



Il giorno ven 7 ott 2022 alle ore 07:26 Christoph Wolf
 ha scritto:

> Dear Matteo,
>
> I just tested with 22.04 and intel one API and the gitlab version with a
> simple  ./configure --prefix=... worked without issues. On an older machine
> I had some obscure error related to git, which was simply solved by
> updating git.
>
> check if your LD_LIBRARY_PATH is properly set; I had some issues with
> oneAPI not overwriting an older library location (no clue why).
>
> HTH!
> Chris
>
> --
> Group Leader "Theory of Quantum Systems at Surfaces"
> IBS Center for Quantum Nanoscience
> Seoul, South Korea
>
> ___
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

[QE-users] compiling QE with Ubuntu 22.04

[Matteo Cococcioni]

Dear QE users,

has anybody managed to compile QE (any version) on a desktop with Ubuntu
22.04 (and intel compilers, mkl libraries)? Unfortunately I had the bad
idea to upgrade Ubuntu to the latest version and the compilation stopped
working.
Apparently the problem is sort of known. So I'm just wondering if anybody
managed to find a way around it. I haven't had much luck so far.
If I remember correctly it complains about The FoX library and the c
compiler.

Thanks,

Matteo

-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Applicability of DFT+U+J to Anisotropy Calculations

[Matteo Cococcioni]

Dear Peter,

I don't know how to answer your question 1). As for 2) maybe this paper can
help you:

PHYSICAL REVIEW B 96, 165132 (2017); DOI: 10.1103/PhysRevB.96.165132

Best regards,

Matteo



Il giorno ven 18 feb 2022 alle ore 03:30 Peter Stoeckl via users <
users@lists.quantum-espresso.org> ha scritto:

> Dear all,
>
> In recent calculations I have been attempting to calculate uniaxial
> magnetocrystalline anisotropies in transition-metal magnetic compounds
> using DFT+U method.
>
> As I understand it, these calculations require (a) non-collinear spins
> `noncolin = .true.` and (b) DFT+U with both U and J parameter
> `lda_plus_u_kind = 1`, as the simpler  `lda_plus_u_kind = 0` is
> incompatible with non-collinear spin calculations.
> (This is occasionally inconvenient, as DFT+U+J itself is not supported for
> structural relaxations.)
>
> 1. Are there any known issues (or theoretical concerns) with using DFT+U+J
> in calculations of magnetic anisotropy in QE?
>
> 2. For reference, I calculate E_MCA = E_IP – E_OP, i.e. the difference in
> (SCF) energy between configurations with in-plane and out-of-plane
> magnetization respectively, rather than the perhaps easier force theorem
> approach. While I don't expect this to change much, does this affect the
> considerations from (1), if any?
>
> Any information (or corrections) regarding the above points would be
> greatly appreciated.
>
> Peter Stoeckl
> PhD Candidate, Department of Physics
> University of Minnesota
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] convergence issue in DFT_U+V calculation

[Matteo Cococcioni]

Dear Bhamu,

you better use two different kinds for the Fe in octahedral sites: one for
2+ the other for 3+. they are likely to have different U's as well.

Matteo


Il giorno mer 1 dic 2021 alle ore 11:34 Dr. K. C. Bhamu 
ha scritto:

> Dear Dr. Matteo,
>
> Thank you very much for the quick response.
>
> Yes, I am doing vc-relax in between each step.  Doing vc-relax without
> adopting geometry information from the previous run. I am only supplying
> the HP file containing U+V obtained from the previous run for the vc-relax
> for the next step.
>
> Fe1 (octahedral coordination) atom has a mixed charge state (Fe3+ and
> Fe2+).
> The magnetic moment of Fe1( Fe3+) cancels out with Fe2 (tetrahedral
> coordination; all Fe3+) and the resultant magnetic moment comes from Fe1
> (2+) atoms.
> According to Ref. [1]
> <https://www.sciencedirect.com/science/article/abs/pii/S0039602812000544>,
> I set all Fe1 as up and all Fe2 as down spins.
>
> Do you think my input still has some issues?
>
> ---
> I am providing some additional information here.
>
> Additional information:
>
> Ref. [1]
> <https://www.sciencedirect.com/science/article/abs/pii/S0039602812000544>
> Just below Fig. 3 it is mentioned that "For Fe3O4 having ferrimagnetic
> property, the spin of the octahedral and tetrahedral Fe was set as up and
> down, respectively."
>
>
> Relevant para from Ref. [2]
> <https://link.springer.com/article/10.1134%2FS1027451010030079> is as
> below:
> Fe2+ cations in the face-centered cubic lattice formed by oxygen anions
> occupy octahedral sites, while Fe3+ cations are distributed between
> octahedral and tetrahedral sites. The trivalent Fe3+ ion is in the state
> with a spin S = 5/2 and zero orbital moments. The bivalent Fe2+ ion has a
> spin of 2, and its contribution comes to ~4μB unless one considers a
> certain possible contribution from the orbital moment [2]. The measured
> value of the magnetic moment for magnetite is 4.1μB. The magnetic moments
> of Fe3+ ions are antiparallel to each other, and the observed moment is
> determined by Fe2+ ions only (Fig. 1).
>
>
> Thanks and regards
> Bhamu
>
>
>
> On Wed, Dec 1, 2021 at 2:17 PM Matteo Cococcioni <
> matteo.cococci...@unipv.it> wrote:
>
>> the fourth iteration does not look too good to me as the U for Fe2 is
>> suddenly going from 4.31 to 0.7.
>> Fe3O4 is a difficult system of its own. are you sure that all the Fe1 are
>> of the same kind (3+)? The system is for sure
>> a mixed valence one but I don't remember how this matches its magnetic
>> structure. Are you relaxing the structure in between?
>> Maybe because of the structure changes hp is not recognizing the
>> neighbors it had before for each Fe.
>>
>> Regards,
>>
>> Matteo
>>
>> Il giorno mer 1 dic 2021 alle ore 06:07 Dr. K. C. Bhamu <
>> kcbham...@gmail.com> ha scritto:
>>
>>> Dear Iurii,
>>> This is from the calculation without nbnd in QE input file (QE input and
>>> HP input are supplied at the end of this email).
>>> I am trying to get a converged value of U+V. Up to four steps, all the
>>> calculations seem to be fine (other than the converged value of U+V). But
>>> in the 5th step, I see that my calculations are not converging.
>>>
>>> I am getting this message:
>>>   atom #  5   q point #   3   iter # 180
>>>   chi:   1 -83.8242814567   residue:  103.6191835332
>>>   chi:   2 -83.8242814548   residue:  103.6191835384
>>>   chi:   3 **   residue:  381.0626501229
>>>   chi:   4 **   residue:  326.7198566114
>>>   chi:   5 317.5473216386   residue:  329.6382092529
>>>   chi:   6 **   residue:  580.5784405595
>>>   chi:   7   9.0496504843   residue:1.9763844786
>>>   chi:   8  -6.2884312048   residue:   21.8495062869
>>>   chi:   9   9.0496505082   residue:1.9763845088
>>>   chi:  10  -6.2884312084   residue:   21.8495062832
>>>   chi:  11  10.2338160751   residue:7.3557134894
>>>   chi:  12  -5.1687829951   residue:   22.9825921172
>>>   chi:  13   6.7503553298   residue:7.1360232476
>>>   chi:  14  -3.9982889995   residue:   27.0388948104
>>>   Average number of iter. to solve lin. system:   23.6
>>>   Total CPU time : 63284.6 s
>>> ###
>>>   atom #  5   q point #   3   iter # 274
>>>   chi:   1 **   residue:  **
>>>   chi:   2 

Re: [QE-users] convergence issue in DFT_U+V calculation

[Matteo Cococcioni]

gauss =   0.022
>   ecutrho =   320
>   ecutwfc =   40
>   occupations = 'smearing' ,smearing = 'mp'
>   ibrav = 0
>   nat = 14
>   nosym = .false.
>   ntyp = 3
> nspin=2
>   starting_magnetization(1) =   0.8
>   starting_magnetization(2) =   -0.8
>   starting_magnetization(3) =   0.0
>
>   lda_plus_u = .true.,
>   lda_plus_u_kind = 2,
>   U_projection_type = 'ortho-atomic',
>   !Hubbard_V(1,1,1) = 1.d-8
>   !Hubbard_V(5,5,1) = 1.d-8
>   !Hubbard_V(7,7,1) = 1.d-8
> Hubbard_parameters = 'file'
>
>
> /
> &ELECTRONS
>   conv_thr =   1.00d-06
>   electron_maxstep = 400
>   mixing_beta =   1.50d-01
> /
> &IONS
> ion_dynamics = 'bfgs'
>  /
> &CELL
> /
>
> ATOMIC_SPECIES
> Fe1 55.845 Fe.pbe-nd-rrkjus.UPF
> Fe2 55.845 Fe.pbe-nd-rrkjus.UPF
> O  15.9994 O.pbe-rrkjus.UPF
> ATOMIC_POSITIONS (crystal)
> Fe1   0.00   -0.00   -0.00
> Fe1   0.500.000.00
> Fe1   0.9998920.500216   -0.00
> Fe1   0.650.560.500115
> Fe2   0.37499937210.37499933490.3750019210
> Fe2   0.62500062250.62500065320.6249981020
> O 0.24548684150.24548683990.2454949640
> O 0.75451318450.75451310980.7545050345
> O 0.76353135460.24548683990.2454949640
> O 0.23646867130.75451310980.7545050345
> O 0.24548683070.76353137460.2454949640
> O 0.75451325230.2364686217    0.7545050345
> O 0.24549085930.24549082220.7635274591
> O 0.75450906290.75450917410.2364725394
>
> CELL_PARAMETERS (angstrom)
>5.944682649   0.0   0.0
>2.972341325   5.148246192   0.0
>2.972341325   1.716082064   4.853885701
>
> K_POINTS automatic
> 7 7 7 0 0 0
>
>
> Regards
> Bhamu
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Regarding U in self-consistant and site dependent

[Matteo Cococcioni]

Dear Anish

Il giorno mar 23 nov 2021 alle ore 07:10 Anish Das 
ha scritto:

> Dear experts,
>
> I am interested in calculating Hubbard-U in self consistent and and site
> dependent manner as i am dealing with local point defect and expecting
> different charged states near the defect. First, I activated the U
> calculation machinaries by applying very small U value (10^-8).Then I
> perturbed the inequivalent open-shell Hubbard sites and got 1st shot of U
> values (for different sites). Then I am supposed to use new values of U and
> again go for the 2nd shot U calculation.
>
> Now my questions are.
>
> 1) Should i relax the structure with U values calculated from 1st shot
> then go for the 2nd shot? Or i just simply plugin the new U, do SCF and go
> for the 2nd shot U-calculation. Dr. Iurii Timrov mentioned to relax the
> structure everytime with new U values in his paper. But my structure is
> large and has 52 Hubbard sites (159 total atoms).
>
>
there is no rule. depends on your system and on what you want to do. In
principles there is always some depenence of U on the structure (and
viceversa). How large this dependence is nobody knows before testing.


> 2) As i mentioned earlier that my system has 52 inequivalent Hubbard
> sites, so 1st i perturbed the all sites and get the 1st shot of U. Then i
> relaxed the structure with new U's. Now after the relaxation when i check
> the inequivalent Hubbard sites for 2nd shot U calculation (by hp.x), it is
> now showing i have 48 Hubbard sites (instead of 52) to be perturbed. My
> question is, should i need to perturb the 52 sites (determined during the
> 1st shot) or 48 sites (determined during 2nd shot calculation)?
>

probably your crystal has become more symmetric and Hubbard atoms got a
more similar environment to one another. that can happen. Probably your
starting structure was a bit disordered and its now going to the near
symmetric minimum of energy. Just guessing.

Please add your affiliation.

Hope this helps.

Matteo


>
> Thanking you
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Negative pressure convention

[Matteo Cococcioni]

Dear Valeria,

negative pressures mean that the lattice wants to contract (the energy is
lower at smaller volumes)

Best,

Matteo

Il giorno mar 19 ott 2021 alle ore 05:24 valeria arteaga muñiz <
valitze...@hotmail.com> ha scritto:

> Hello everyone,
>
>
>
> I am trying to run some MD with pw.x, and I am modifying the lattice
> parameter of my cell until I reach 60 kBar. However, I was noticing that it
> printed some negative pressures. I was wondering if the convention is that
> negative pressure indicates expansion, or what would be the case?
>
>
>
>
>
>
>
> Thank you in advance,
>
>
>
> Valeria
>
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Hubbard-U QE vs VASP

[Matteo Cococcioni]

Dear Jhon,

I would be quite surprised if there is a sign-convention mismatch between
the two implementations.
Please keep in mind that, even if you use the same type of pseudootentials,
there is no guarantee that the same U should lead to the
same result (actually this is not the case most often). The value of U
depends on all the details of the calculations and of the pseudopotnetial.
Of course, It would be interesting to compare the two codes on exactly the
same pseudopotential but I am afraid this is not (yet) possible.
If you want to compute it (which I recommend) please consider using the
hp.x code (now part of the QE distribution) that allows you to determine
its value
using a dfpt implementation of linear response theory which is very
efficient and user-friendly (PRB 103, 045141 (2021); PRB98, 085127 (2018)).
Another thing I recommend to use with QE is orthogonalized atomic orbitals
(U_projection_type = 'ortho-atomic') for which the code now has forces and
stresses
(PRB 102, 235159 (2020)).
Please keep in mind also (and pehaps this makes up for most of the
differences you observe) that VASP uses the the projectors of the
seudopotentials  (of PAW type
mostly) to define the atomic occupations then used in the Hubbard
correction. In QE atomic wavefunctions are instead mostly used to project
Kohn-Sham states on.
If you want a stricter comparison between the two perhaps you should use
U_projection_type = 'pseudo' in QE (use PPs containing wavefunctions - see
INPUT_PW.txt
for more details).

Best regards,

Matteo


Il giorno lun 11 ott 2021 alle ore 01:37 Jhon Gonzalez 
ha scritto:

> Hi,
>
> Perhaps this is a bit off-topic, there is an issue when comparing LDA+U
> results in 2D-materials between Quantum-ESPRESSO and VASP.
> For V2C monolayers, CrI3 mono- and bi-layers, the magnetic stability changes
> and it is impossible to reproduce the results.
>
> For the V2C monolayer with U = 4 eV, while with quantum-ESPRESSO (US and
> PBE), I find that the ground-state
> (GS) solution is FM and the AF solution is about 1 eV above; with VASP U=4
> eV (LDATYPE=2), I find that the GS solution
> is AF and the FM state is 1 eV above (in agreement with
> dx.doi.org/10.1021/jp507336x).
>
> Following the discussion on the implementation of Hubbard's interaction:
> https://lists.quantum-espresso.org/pipermail/users/2020-May/044521.html
> There, it is suggested that in QE the Hubbard-U tends to decrease the gap,
> while in VASP it tends to open it.
> And inspired by the discussion
> http://grandcentral.apam.columbia.edu:/tutorials/dft_procedures/linear_response_u/index.html
>
> there they mention an "empirically is a difference in sign convention". I
> tried a VASP calculation with U = -4 eV, and I found an
> FM GS-solution followed by an AF solution 0.3 eV above, following the QE
> stability order.
>
> From my experience comparing QE results with CrI3 experiments, it seems
> that QE uses the proper sign convention for the U term.
> However, I do not have any evidence for this.
>
> I am currently exploring the use of hybrid functionals to address this
> issue, is there an elegant way to settle this dispute?
>
> Best,
>
>
> Jhon W. González
>
> Departamento de Física
> Universidad Técnica Federico Santa María
> VALPARAISO-CHILE
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Regarding exchange interaction parameter

[Matteo Cococcioni]

Dear Soumyakanta,

if you only use Ueff you don't need any J. Use lda_plus_u_kind = 0. With
this choice you can also use Hubbard_J0. This is the one from PRB 84,
115108 (2011).
with lda_plus_u_kind = 1 you can use Hubbard_U and Hubbard_J. This is the
implementation most common in literature (see Liechtenstein, et al. PRB
1995).
Best regards,

Matteo


Il giorno mar 4 mag 2021 alle ore 07:04 SOUMYAKANTA PANDA via users <
users@lists.quantum-espresso.org> ha scritto:

> Hi users,
> I want to calculate the magnetic properties of a system by
> taking
>  Ueff = U - J value. To do this which Hubbard parameter  should i use
> Hubbard J0 or Hubbard J, and what is the basic difference between these two
> parameters ?
>
> Regards,
> Soumyakanta Panda
> Research Scholar
> Nano Magnetism and Magnetic Materials Laboratory
> IIT Bhubaneswar, India
>
> --
> *Disclaimer: *This email and any files transmitted with it are
> confidential and intended solely for the use of the individual or entity to
> whom they are addressed. If you have received this email in error please
> notify the system manager. This message contains confidential information
> and is intended only for the individual named. If you are not the named
> addressee you should not disseminate, distribute or copy this e-mail.
> Please notify the sender immediately by e-mail if you have received this
> e-mail by mistake and delete this e-mail from your system. If you are not
> the intended recipient you are notified that disclosing, copying,
> distributing or taking any action in reliance on the contents of this
> information is strictly prohibited.
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] U calculation for Cd based material

[Matteo Cococcioni]

Dear Sergey,

Cd has a full d shell. Being probably deep below the gap or Fermi level, d
states are not easy to perturb and the linear-response approach implemented
in hp.x
does not work for these cases. Unless one lifts them up (e.g., with a
sufficiently high Hubbard_alpha) closer to the edge of the valence band
preliminarily. But of course this might corresponds to a significant
perturbation of the electronic structure of the system.

Best regards,

Matteo


Il giorno mer 31 mar 2021 alle ore 21:11 Sergey Lisenkov 
ha scritto:

> Dear users,
>
> I calculated U correction for Cd (Cd based MOF), using HP code (version
> 6.7, ONCVPS pseudopotentials).
>
> If I use "ortho-atomic" projection type, then calculated U=42 eV
> if I use "atomic" projection type, then calculated U=71 eV
>
> these results do not depend on nq mesh.
>
> Those are, obviously wrong values and I'm trying to understand why. Is it
> possible that for this material U correction is not needed?
>
> Thanks,
>  Sergey
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Am with DFT+U+SOC

[Matteo Cococcioni]

Dear Malte,

unfortunately I don't know how to answer to your question. I don't know
this specific implementation very well.
My best guess is that the first 7 entries are for the spin-up component of
the wfc and the other 7 for spin-down, with non trivial off diagonal terms
(your L+1/2, L-1/2 scheme). Maybe you can reconstruct what has been done by
comparing a spin-collinear calculation (nspin = 2) with a non collinear one
with all the spin along z. They should give the same result (put J = 0 of
course).
Perhaps people who contributed the implementation of the DFT+U with
non-collinear spin can tell you more about this.

Best regards,

Matteo

Il giorno sab 13 mar 2021 alle ore 09:53 Malte Sachs <
malte.sa...@chemie.uni-marburg.de> ha scritto:

> Dear Matteo,
>
> thank you for your reply. I should reformulate my issue. I am not sure how
> to interpret the 14x14 occupation matrix that results from SOC. In scalar
> relativistic calculations the two 7x7 matrices refer to the 7 spatial
> orbitals of spin up and down. How it is done with SOC? Do the entries now
> refer to the L+1/2 and L-1/2 levels? In this case, I would interpret the
> occupation matrix as having 7 entries with L+1/2 and 7 entries with L-1/2.
> However, in case of j-j splitting the f-orbitals split into 6 j_5/2 and 8
> j_7/2 states.
> This is the point, where I am confused. In one case I have 7 L+1/2 and 7
> L-1/2 states and in the other case 6 and 8, so that I do not know how to
> set up a starting occupation where all j_5/2 levels are occupied. Where is
> my mistake in thinking?
>
> Best regards,
> Malte
>
> Am 12.03.21 um 22:07 schrieb Matteo Cococcioni:
>
> Dear Malte,
>
> I'm not sure what you mean by "struggling to set initial conditions".
> I'm not even sure that starting_ns_eigenvalue works in the non_colin case.
> However keep in mind that the occupation matrix 14x14 now (the two spin
> are treated together).
> You need to check the eigenvalues of the occupation matrix after the first
> iteration
> to see how the eigenstates are ordered and whether (and how) you need to
> adjust it
> using starting_ns_eigenvalue.
>
> HTH
>
> Best,
>
> Matteo
>
>
> Il giorno ven 12 mar 2021 alle ore 20:05 Malte Sachs <
> malte.sa...@chemie.uni-marburg.de> ha scritto:
>
>> Dear DFT+U experts,
>>
>> I want to study metallic Am with DFT+U+SOC. It should be non-magnetic
>> with the 5f_j5/2 level fully occupied. However, I am struggling to set
>> this as initial configuration using the starting_ns_eigenvalue option in
>> QE. Is this possible at all with this option or do I misunderstand
>> something?
>>
>> Best regards,
>>
>> Malte
>>
>> --
>> Malte Sachs
>> Anorganische Chemie, Fluorchemie
>> Philipps-Universität Marburg
>> Hans-Meerwein-Straße 4
>> 35032 Marburg (Paketpost: 35043 Marburg)
>> Tel.: +49 (0)6421 28 - 25 68 0
>> http://www.uni-marburg.de/fb15/ag-kraus/
>>
>>
>> ___
>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>> users mailing list users@lists.quantum-espresso.org
>> https://lists.quantum-espresso.org/mailman/listinfo/users
>
>
>
> --
> Matteo Cococcioni
> Department of Physics
> University of Pavia
> Via Bassi 6, I-27100 Pavia, Italy
> tel +39-0382-987485
> e-mail matteo.cococci...@unipv.it 
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list 
> users@lists.quantum-espresso.orghttps://lists.quantum-espresso.org/mailman/listinfo/users
>
>
> --
> Malte Sachs
> Anorganische Chemie, Fluorchemie
> Philipps-Universität Marburg
> Hans-Meerwein-Straße 4
> 35032 Marburg (Paketpost: 35043 Marburg)
> Tel.: +49 (0)6421 28 - 25 68 0http://www.uni-marburg.de/fb15/ag-kraus/
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Am with DFT+U+SOC

[Matteo Cococcioni]

Dear Malte,

I'm not sure what you mean by "struggling to set initial conditions".
I'm not even sure that starting_ns_eigenvalue works in the non_colin case.
However keep in mind that the occupation matrix 14x14 now (the two spin are
treated together).
You need to check the eigenvalues of the occupation matrix after the first
iteration
to see how the eigenstates are ordered and whether (and how) you need to
adjust it
using starting_ns_eigenvalue.

HTH

Best,

Matteo


Il giorno ven 12 mar 2021 alle ore 20:05 Malte Sachs <
malte.sa...@chemie.uni-marburg.de> ha scritto:

> Dear DFT+U experts,
>
> I want to study metallic Am with DFT+U+SOC. It should be non-magnetic
> with the 5f_j5/2 level fully occupied. However, I am struggling to set
> this as initial configuration using the starting_ns_eigenvalue option in
> QE. Is this possible at all with this option or do I misunderstand
> something?
>
> Best regards,
>
> Malte
>
> --
> Malte Sachs
> Anorganische Chemie, Fluorchemie
> Philipps-Universität Marburg
> Hans-Meerwein-Straße 4
> 35032 Marburg (Paketpost: 35043 Marburg)
> Tel.: +49 (0)6421 28 - 25 68 0
> http://www.uni-marburg.de/fb15/ag-kraus/
>
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Regarding GGA+U+SOC implementation in Quantum espresso code.

[Matteo Cococcioni]

Dear Soumyakanda,

from a very quick look at your input it seems fine to me. Does it crash
after some iterations or right at the start?
do you get convergence if you switch off the U or the SOC?

Good luck,

Matteo


Il giorno mer 3 mar 2021 alle ore 11:17 SOUMYAKANTA PANDA via users <
users@lists.quantum-espresso.org> ha scritto:

> Hi users,
> I am trying to calculate the band structure and density of states by using
> GGA+U+SOC for the sriro3 compound.
> however
> i
> am getting
> an error message like :  Internal error, convergence  has not been
> achieved.
> Is GGA+U+SOC implemented on Quantum espresso ?
> here i am attaching my input file kindly tell me the path
> to
> get the solutions.
>
> Best Regards,
> Soumyakanta Panda
> Research Scholar
> Nano Magnetism and Magnetic Materials Laboratory
> IIT Bhubaneswar
>
> --
> *Disclaimer: *This email and any files transmitted with it are
> confidential and intended solely for the use of the individual or entity to
> whom they are addressed. If you have received this email in error please
> notify the system manager. This message contains confidential information
> and is intended only for the individual named. If you are not the named
> addressee you should not disseminate, distribute or copy this e-mail.
> Please notify the sender immediately by e-mail if you have received this
> e-mail by mistake and delete this e-mail from your system. If you are not
> the intended recipient you are notified that disclosing, copying,
> distributing or taking any action in reliance on the contents of this
> information is strictly prohibited.
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] constrained magnetization with non-colin and spin-orbit

[Matteo Cococcioni]

Dear Cyrille,

Il giorno lun 18 gen 2021 alle ore 11:42 BARRETEAU Cyrille <
cyrille.barret...@cea.fr> ha scritto:

> Dear Matteo,
> Non collinear calculations are usually very difficult to converge with QE
> (usually codes based on localized basis set are easier to converge since I
> guess there are less degrees of freedom..).
> This is even more difficult in finite systems such as clusters or
> molecules where you can often have multiple magnetic states.
>

Yes, in fact this is also my case: many magnetic states.


> Did you try to perform non-collinear calculations without SOC? Just to
> check that collinear configurations converge and are independent of the
> magnetization angle?
>

I only got convergence with SOC. without SOC I haven't tried yet but I
will. I have to go back to the scalar-relativistic PP for that, right?

Thanks,

Matteo



> Cyrille
>
> 
> *Cyrille Barreteau*
> CEA Saclay, IRAMIS, SPEC Bat. 771
> 91191 Gif sur Yvette Cedex, FRANCE
> 
> +33 1 69 08 38 56 /+33  6 47 53 66 52  (mobile)
> email: cyrille.barret...@cea.fr
> Web: http://iramis.cea.fr/Pisp/cyrille.barreteau/
> 
> --
> *De :* users [users-boun...@lists.quantum-espresso.org] de la part de
> Matteo Cococcioni [matteo.cococci...@unipv.it]
> *Envoyé :* lundi 18 janvier 2021 11:05
> *À :* Quantum ESPRESSO users Forum
> *Objet :* Re: [QE-users] constrained magnetization with non-colin and
> spin-orbit
>
> Dear Cyrille,
>
> thanks for your reply and advice.
>
> Il giorno lun 18 gen 2021 alle ore 10:25 BARRETEAU Cyrille <
> cyrille.barret...@cea.fr> ha scritto:
>
>> Dear Matteo
>>
>> If I understand well you want to calculate the magnetic anisotropy of a
>> magnetic molecule.
>>
>
> Yes, that's correct
>
>
>> I am not sure I have understood well the way you proceed when you say
>> that you "start" from a collinear lsda.
>>
>>
> Well, I tried to start a non collinear calculation of this system from
> scratch, but I could never achieve convergence. The convergence with lsda
> is much more robust and using tot_magnetization I could achieve both a
> ferromagnetic and an antiferromagnetic ground state. Then I tried to use
> the charge-density of these ground states to initialize the non-collinear
> calculation (of course after updating the Mo PP to its fully relativistic
> version) with spin-orbit. This way I manage to converge to the same AFM and
> FM ground state with the non-collinear calculation. Now I want to use these
> calculations as starting points to take the magnetic moments away from the
> z direction to which they are (anti)aligned.
>
>
>> I would say that you can try two strategies:
>>
>> i) using the force theorem as implemented in QE (one scf lsda calculation
>> and then nscf with SOC starting from different theta angles..)
>>
>
> ok, I hadn't thought of this. Maybe it's sufficient to estimate the MAE.
> If you initialize just the theta angle (angle1) will the modulus of the
> magnetic moment be preserved with respect to the lsda or collinear ground
> state it starts from? How does the code choose the angle phi (angle2) in
> this case? In presence of SOC this also might make a difference and
> contribute to the MAE (unless the system has a cylindrical symmetry around
> the easy axis, which is not my case).
>
>
>> ii) use the magnetic constraint with penalization parameter lambda and
>> perform a scf calculation. It will be more delicate but maybe more precise
>> (not sure since you might face convergence problems)
>>
>>
> This is what I was trying to do (see above, also): I am trying to change
> angle1 with lambda. I wanted to do a scf calculation to leave the system
> free to chose angle2. But the convergence is very delicate. Actually there
> seems to be no finite contribution to the potential from the constraint, so
> the calculation goes on for a while without changing the angles from their
> starting value and then suddenly crashes (not sure why). It seems that the
> variable pointlist is never different from 0 in my case which causes the
> potential to be insensitive to lambda. But I haven't yet understood why.
>
> thanks again.
>
> Best regards,
>
> Matteo
>
>
>
>> best
>> Cyrille
>>
>>
>>
>> ========
>> *Cyrille Barreteau*
>> CEA Saclay, IRAMIS, SPEC Bat. 771
>> 91191 Gif sur Yvette Cedex, FRANCE
>> 
>> +33 1 69 08 38 56 /+33  6 47 53 66 52  (mobile)
>> email: cyrille.barret...@cea.fr
&

Re: [QE-users] constrained magnetization with non-colin and spin-orbit

[Matteo Cococcioni]

Dear Cyrille,

thanks for your reply and advice.

Il giorno lun 18 gen 2021 alle ore 10:25 BARRETEAU Cyrille <
cyrille.barret...@cea.fr> ha scritto:

> Dear Matteo
>
> If I understand well you want to calculate the magnetic anisotropy of a
> magnetic molecule.
>

Yes, that's correct


> I am not sure I have understood well the way you proceed when you say that
> you "start" from a collinear lsda.
>
>
Well, I tried to start a non collinear calculation of this system from
scratch, but I could never achieve convergence. The convergence with lsda
is much more robust and using tot_magnetization I could achieve both a
ferromagnetic and an antiferromagnetic ground state. Then I tried to use
the charge-density of these ground states to initialize the non-collinear
calculation (of course after updating the Mo PP to its fully relativistic
version) with spin-orbit. This way I manage to converge to the same AFM and
FM ground state with the non-collinear calculation. Now I want to use these
calculations as starting points to take the magnetic moments away from the
z direction to which they are (anti)aligned.


> I would say that you can try two strategies:
>
> i) using the force theorem as implemented in QE (one scf lsda calculation
> and then nscf with SOC starting from different theta angles..)
>

ok, I hadn't thought of this. Maybe it's sufficient to estimate the MAE. If
you initialize just the theta angle (angle1) will the modulus of the
magnetic moment be preserved with respect to the lsda or collinear ground
state it starts from? How does the code choose the angle phi (angle2) in
this case? In presence of SOC this also might make a difference and
contribute to the MAE (unless the system has a cylindrical symmetry around
the easy axis, which is not my case).


> ii) use the magnetic constraint with penalization parameter lambda and
> perform a scf calculation. It will be more delicate but maybe more precise
> (not sure since you might face convergence problems)
>
>
This is what I was trying to do (see above, also): I am trying to change
angle1 with lambda. I wanted to do a scf calculation to leave the system
free to chose angle2. But the convergence is very delicate. Actually there
seems to be no finite contribution to the potential from the constraint, so
the calculation goes on for a while without changing the angles from their
starting value and then suddenly crashes (not sure why). It seems that the
variable pointlist is never different from 0 in my case which causes the
potential to be insensitive to lambda. But I haven't yet understood why.

thanks again.

Best regards,

Matteo



> best
> Cyrille
>
>
>
> 
> *Cyrille Barreteau*
> CEA Saclay, IRAMIS, SPEC Bat. 771
> 91191 Gif sur Yvette Cedex, FRANCE
> 
> +33 1 69 08 38 56 /+33  6 47 53 66 52  (mobile)
> email: cyrille.barret...@cea.fr
> Web: http://iramis.cea.fr/Pisp/cyrille.barreteau/
> ========
> --
> *De :* users [users-boun...@lists.quantum-espresso.org] de la part de
> Matteo Cococcioni [matteo.cococci...@unipv.it]
> *Envoyé :* dimanche 17 janvier 2021 11:09
> *À :* Quantum ESPRESSO users Forum
> *Objet :* [QE-users] constrained magnetization with non-colin and
> spin-orbit
>
>
> Dear all,
>
> I am trying to run some calculations on a molecule with two magnetic ions
> (Mo) and I want to use the non collinear spin with spin-orbit to calculate
> the energy needed to change their direction. Starting from a collinear
> (lsda) calculation I managed to converge the non-collinear one in a
> ferromagnetic configuration, with magnetic moments aligned along z. Now I
> am using this ground state as starting point for a calculation where one or
> both spins are somehow deviated from the z direction. Following the
> instructions in INPUT_PW I am using the following settings (in &system):
>
> noncolin = .true.
> lspinorb=.true.
> angle1(1) = 30.0
> angle1(2) = 30.0
> constrained_magnetization = 'atomic direction'
> lambda = 1.0
>
> where species 1 and 2 correspond to the two Mo, angle1 is the angle I want
> to have between z and the final magnetization, lambda is the strength of
> the quadratic constraint.
>
> If I start from the potential of the ground state with the magnetization
> along z, the code starts with no problem and even pretends to converge for
> a number of iterations. Then suddenly the energy explodes and the code
> crashes saying that there are too many not converged eigenvalues.
> While it seems converging nothing relevant seems to happen to angles: the
> constraint energy remains almost the same and the magnetization of both
> atoms maintains its original directio

[QE-users] constrained magnetization with non-colin and spin-orbit

[Matteo Cococcioni]

Dear all,

I am trying to run some calculations on a molecule with two magnetic ions
(Mo) and I want to use the non collinear spin with spin-orbit to calculate
the energy needed to change their direction. Starting from a collinear
(lsda) calculation I managed to converge the non-collinear one in a
ferromagnetic configuration, with magnetic moments aligned along z. Now I
am using this ground state as starting point for a calculation where one or
both spins are somehow deviated from the z direction. Following the
instructions in INPUT_PW I am using the following settings (in &system):

noncolin = .true.
lspinorb=.true.
angle1(1) = 30.0
angle1(2) = 30.0
constrained_magnetization = 'atomic direction'
lambda = 1.0

where species 1 and 2 correspond to the two Mo, angle1 is the angle I want
to have between z and the final magnetization, lambda is the strength of
the quadratic constraint.

If I start from the potential of the ground state with the magnetization
along z, the code starts with no problem and even pretends to converge for
a number of iterations. Then suddenly the energy explodes and the code
crashes saying that there are too many not converged eigenvalues.
While it seems converging nothing relevant seems to happen to angles: the
constraint energy remains almost the same and the magnetization of both
atoms maintains its original direction (aside small fluctuations). The same
behavior is observed independently from the value of lambda (which is very
strange) and beta (the mixing parameter).

looking into the code (add_bfield.f90) the implementation of the constraint
seems fine, as far as I can tell (except that the code tries to constraint
all magnetic moments once a lambda is present, which I fixed), and the
potential seems to get a term from the constraint on magnetization. So I
would expect it to do something.

Does anyone have any experience with this type of calculations? What am I
missing or not doing right? Thanks in advance for any help/advice.

Best regards,

Matteo

-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] "wrong offset" error when using SG15 pseudo

[Matteo Cococcioni]

Dear Sergey,

try to give a look inside your SG15 pseudopotential for Mn. For some reason
the code does not find the d states it is expecting to use for the +U
correction. If you do a calculation with dft_plus_u = .false. can you
compute the projected density of states? Do you get anything on the 3d
states? If projwfc finds them then also pw should find the 3d states.

Best,

Matteo



Il giorno ven 30 ott 2020 alle ore 02:04 Sergey Lisenkov 
ha scritto:

> Hello all,
>
> I tried to use DFT+U with SG15 pseudopotentials (from SG15 library, 2020
> version). First element in my structure is "Mn". I immediately got this
> error message:
>
>
> %%
>  Error in routine offset_atom_wfc (1):
>  wrong offset
>
>  
> %%
>
> Looking at the archives for similar error message, I found that it is
> related that atomic element is not defined in "tabd.f90". But certainly Mn
> element is implemented.
>
> When I changed pseudopotentials to different one, no such message appears.
>
> Could it mean that SG15 pseudopotentials are not suitable for the DFT+U
> calculations?
>
> Thanks,
>  Sergey
>
> USF
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] DFT+U calculation and Hubbard_J0 parameter

[Matteo Cococcioni]

Dear Yuvam

please see below.


Il giorno mer 28 ott 2020 alle ore 10:58 Yuvam Bhateja 
ha scritto:

> Hello experts,
>
> I have been using Quantum ESPRESSO for my project and now I wanted to
> include DFT+U in my calculation.
>
> I was using lda_plus_u_kind = 0 (which only uses Hubbard_U parameter)
> along with Hubbard_J0.
> For example-
>
> lda_plus_u_kind=0
> Hubbard_U(1)=5.0
> Hubbard_J0(1)=0.48
>
> Using the above configuration my system converged perfectly.
>
> I wanted to know if I am doing something wrong here? Will the value of
> Hubbard_J0 be even considered if I am using lda_plus_u_kind=0?
>


why do you think there is something wrong?
In order to understand whether J0 makes any difference just try without it
and compare the results.



>
> I wished to replicate the results in other softwares like SIESTA which
> only uses rotationally invariant scheme (i.e., equivalent to lda_plus_u=1).
> Can I use values of U=5.0 and J=0.48 as mentioned above in other DFT codes?
>

strictly speaking they are not the same thing (unless J = J0 = 0). here is
the reference for J0: PHYSICAL REVIEW B 84, 115108 (2011). But I don't know
how similar the results would be.

HTH

Matteo




>
> Any suggestions would be very helpful.
>
> Regards
> Yuvam Bhateja
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Computing inner products involving orbitals

[Matteo Cococcioni]

Dear Andrew,

I would first compute | \psi'_l > = U_lm | \psi_m> using some linear
algebra routine (as done in the code in many places by summing over plane
waves), then compute
H |\psi'_l > (e.g., using h_psi.f90), finally the product with < \psi'_n |.
HTH

Matteo


Il giorno mer 7 ott 2020 alle ore 04:27 Andrew Xu 
ha scritto:

> Hi users,
>
> I would like to compute < \psi_n | U^\dagger H U | \psi_m>, where H is the
> KS Hamiltonian, \psi_n, \psi_m are the KS orbitals, and U is some unitary
> operator, by modifying the source code (not done separately through a
> separate Python script, for example), and wanted to ask for some advice. I
> think I can get the \psi_n, \psi_m in reciprocal space, but am not sure how
> to get the bra-ket.
>
> Best regards,
> Andrew
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] two U values for the same element in a system

[Matteo Cococcioni]

Dear Xiongyi,

just list the two Fe atoms as of different kind, for example Fe1 and Fe2,
obviously corresponding to the same pseudopotential. Then you can use two
different values for Hubbard_U. If you don't know which values to use, keep
in mind that the hp.x code of the QE distribution, allows you to compute
them, through linear response.

Best regards,

Matteo

Il giorno mer 23 set 2020 alle ore 03:50 LEUNG Clarence <
liangxy...@hotmail.com> ha scritto:

> Dear QE users,
>
> Recently, I want to study the electronic properties of Prussian blue,
> NaFe[Fe(CN)6].
> It is noted that there are two kind of Fe atom (Fe1 high spin state and
> Fe2 low spin state).
> How can I set two different U value for Fe1 and Fe2?
> Many thanks.
>
> Best regards,
> LIANG Xiongyi
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Ground state of DFT+U

[Matteo Cococcioni]

Dear Malte,

please see below.

Il giorno lun 24 ago 2020 alle ore 19:34 Malte Sachs <
malte.sa...@chemie.uni-marburg.de> ha scritto:

> Dear DFT+U experts,
>
> I am wondering how to know what is the ground state of a DFT+U
> calculation from an ab initio point of view. As approximated DFT is not
> variational I think I cannot use the total energy as an argument.
>
>
This is an open question. DFT+U is only variational at fixed U.


> In my case I have calculated the electronic structure of NdCo in the
> CsCl structure type using QE-6.6. The f-orbitals splits into three
> representations: au, t2u and t2g. For Nd, I expect that it has a valency
> of three and that the t2g orbitals are fully occupied for one spin.
> However, I find that occupying the three t2g orbitals by 2/3 and the au
> orbital by one electron yields a lower energy than the expected
> occupation. So I wonder if I can trust in this "ground state" that is
> against my intuition or if this is a well known effect of DFT+U.
>
>

I know nothing about your system, but it could be a case similar to the
ground state of FeO which we studied it in PRB 71, 035105 (2005).

Hope this helps.

Matteo



> All hints are welcome, best regards,
>
> Malte
>
> --
> Malte Sachs
> Anorganische Chemie, Fluorchemie
> Philipps-Universität Marburg
> Hans-Meerwein-Straße 4
> 35032 Marburg (Paketpost: 35043 Marburg)
> Tel.: +49 (0)6421 28 - 25 68 0
> http://www.uni-marburg.de/fb15/ag-kraus/
>
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Regarding "occupations" keyword in input file

[Matteo Cococcioni]

In addition to what Iurii says, if you use occupation="smearing" the phonon
code will assume your system is metallic and will never compute the
dielectric tensor and Born effective charge which you need, instead to get
the LO-TO splittings at Gamma (non analytic part of the dynamical matrix).

Greetings,

Matteo


Il giorno gio 13 ago 2020 alle ore 20:11 Timrov Iurii 
ha scritto:

> Dear Mohaddeseh,
>
>
> To perform linear response calculations (phonons, calculation of Hubbard
> parameters, etc.) for magnetic insulators, I use the procedure described in
> q-e/HP/examples/example02/README.
>
>
> If you have a gapped system, you should not use smearing, because there
> can be numerical issues (due to the division by zero, because the DOS at
> the Fermi level can be very small using small smearing for insulators, see
> Eq. (79) in Rev. Mod. Phys. 73,  515 (2001)).
>
>
> Greetings,
>
> Iurii
>
>
> --
> Dr. Iurii Timrov
> Postdoctoral Researcher
> STI - IMX - THEOS and NCCR - MARVEL
> Swiss Federal Institute of Technology Lausanne (EPFL)
> CH-1015 Lausanne, Switzerland
> +41 21 69 34 881
> http://people.epfl.ch/265334
> --
> *From:* users  on behalf of
> Mohad Abbasnejad 
> *Sent:* Thursday, August 13, 2020 7:58:21 PM
> *To:* users@lists.quantum-espresso.org
> *Subject:* [QE-users] Regarding "occupations" keyword in input file
>
> Dear QE users,
>
> Hello
>
> I have a general question.
> My structure is Mott hubbard and has a band gap of about 2 eV. It is also
> antiferromagnetic in its ground state.
> I can obtain antiferromagnetic state and the desired band gap with hubbard
> parameters by both ways:
> occupations: smearing
> occupations: fixed
> A) I am wondering whether these occupations can have effect on the phonon
> frequencies?
> B) When is it preferable to use occupation fixed in our calculations?
>
> Any help would be appreciated.
> Thanks in advance.
>
> Regards,
> Mohaddeseh
>
> --
> -
> Mohaddeseh Abbasnejad,
> Assistant Professor of Physics,
> Faculty of Physics,
> Shahid Bahonar University of Kerman,
> Kerman, Iran
> P.O. Box 76169-133
> Tel: +98 34 31322199
> Fax: +98 34 33257434
> Cellphone: +98 917 731 7514
> E-Mail: mohaddeseh.abbasne...@gmail.com
> Website:  academicstaff.uk.ac.ir/moabbasnejad
> -
>
> _______
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] lda_plus_u_kind=2

[Matteo Cococcioni]

This part of the code is still not so user-friendly (in fact still under
improvement).
yes the code recognizes all the neighbors at the same distance and puts the
same V between them. You just need to find one of them in the unit cell and
make sure that that atom (or one of its periodic replicas) belongs to the
proper star of neighbors you are treating with V.
In order to do that it might be a good idea to shift the reference atom to
the center of the cell, so you increase the chances to find one of its
neighbors in the unit cell.

HTH

Matteo

Il giorno sab 18 lug 2020 alle ore 17:38 Andrew Supka 
ha scritto:

> I have been experimenting with the developers version cloned from gitlab.
> I would like to specify a hubbard V between atom1 at the edge of the unit
> cell R=[0,0,0] and a nearest neighbor, atom2, in an adjacent unit cell
> R=[0,0,1]. It appears that the code automatically finds the equivalent
> atoms to the site you put a hubbard U and applies the V to those also.
>
> I have attempted to put the V on the equivalent to atom2 in R=[0,0,0] but
> it assumes I want the V between the two atoms in R=[0,0,0].
>
> I have also tried adding the V using an index corresponding to another
> unit cell. I'm not sure how the indices for the atoms are chosen when the
> algorithm finds equivalent sites.
>
> Is there a simple way to do what I detailed above? Also if I'm way off
> please let me know.
>
> Thank you for any information you can provide.
>
> Andrew Supka
> Postdoc Physics
> Central Michigan University
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] second step of scf in relax calculations didn't converge

[Matteo Cococcioni]

Hello,

it's very difficult to guess what is wrong in your input if you don't show
it.
In any case, if you have converged forces and stresses on cut-off(s) and
number of k-points/smearing, it might be a good idea to tighten your
convergence threshold and reduce the initial trust radius. Maybe your
forces and stresses are so loosely converged and your ionic/cell step so
big that the system moves to a configuration that is difficult to converge.
Or maybe your starting lattice parameter/ionic configuration are very far
from equilibrium and the system tries to make a big jump at the beginning.
Also, have you tried to start a new scf from the new ionic position?

Please add your affiliation

Regards,

Matteo

Il giorno mer 1 lug 2020 alle ore 13:45 Coralie Khabbaz <
khabbaz.cora...@gmail.com> ha scritto:

> Hello,
>
> I am doing a relax calculation on my WN (48 atoms) slab. The first step of
> scf calculations converged but then the second step didn't converge in 1000
> steps (which was my limit). So, the calculations stopped, and I got many
> files (data-file.xml, charge-density.dat, paw.txt,
> spin-polarization.dat...) but no output file. If my first scf step
> converged doesn't that mean that all of my other scf steps should converge
> but need more steps? Or is there a problem in my input file?
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Strong dependance of DFT+U on projector choice

[Matteo Cococcioni]

Dear Julien,

below I offer my point of view on your questions.

Il giorno mer 17 giu 2020 alle ore 16:13 JULIEN, CLAUDE, PIERRE BARBAUD <
julien_barb...@sjtu.edu.cn> ha scritto:

> Dear Users,
> I have recently tried to implement DFT+U on a FAPbI3 system, following the
> work reported in J. Phys. Chem. C 2018, 122, 27340−27349. This is not the
> most canonical use of DFT+U on d orbitals of transition metals. Instead,
> the authors used the Hubbard correction on the I 5p and Pb 6p orbitals to
> empirically fit the experimental band gap.
> Since this is used in conjonction with spin-orbit effects, I have to use
> lda_plus_u_kind=1 (but I keep J=0, which should make it equivalent to using
> the default method if I'm not mistaken). I also had to add the atoms in the
> relevant f90 files as they were not initially included.
>
> When initially trying to correct the band gap, I observed very troubling
> results. The band gap actually reduced from ~0.4 eV (DFT w/SOC) to ~0.3 eV
> (DFT+U w/SOC). Even more frustrating, screening multiple U values made very
> little change on that band gap result, and would always yield values lower
> than the U=0 case... Another disturbing result had to do with the occupancy
> eigenvalues, which reported a total occupation of 3.4 on Pb, seemingly
> making it a "Pb-". This is strange because the bonding in this material has
> an ionic character, and I would expect Pb oxidation state  to tend towards
> a Pb2+ (meaning its occupation should at least go below 2). I tried to
> force different behaviors with lower values for starting_ns_eigenvalue, but
> unsuccessfully.
>


I think all this is related to the fact that you are using +U on p states
that are much more spread than d and probably overlap much more in the
interstitial regions. This probably leads to overestimated occupations
(some "piece" of electrons are counted twice) and, since U tries to
stabilize integer occupations suppressing interatomic hybridization (to
which the band gap might be due), you probably also get a reduced band gap
(see J. Phys. Condens. Matter 22, 055602 (2010) for similar cases). Keep in
mind that, as usual, DFT is not a band gap theory, nor is DFT+U.



>
> I then noted that the projectors I was using were not orthogonalized,
> which makes the interpretation in terms of ionic charges more challenging.
> I tried a run with U_projection_type='ortho-atomic', and this changed the
> results completely. I was able this time to obtain much larger band gaps
> and to find pairs of U value reproducing my experimental band gap easily. I
> do observe an occupation of 1.3 on Pb for those values, which seems more
> realistic too.
>
> However, I am not very comfortable with this. Is it normal for my results
> to be so wildly influenced by the choice of projectors (it seems like a
> somewhat arbitrary choice that should not change completely the results
> obtained). The fact that I can't get anything to work with the default
> option (and especially that the band gap was reduced) is still quite
> disturbing, and makes me question the validity of the results obtained with
> orthonormal projectors.
> Has this strong influence been reported before? Is it the symptom of a
> problem that can invalidate further calculations?
>


the reason why the default option ("atomic") is kept alive is that it is
useful for energy derivatives as forces and stresses. We are working on
that and hopefully in the near future we will also have energy derivatives
for the ortho-atomic case.

Best regards,

Matteo



> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Hubbard U orbital order for l=3 states

[Matteo Cococcioni]

If it hasn't changed recently, the order of orbitals should be given by
growing values of |m|, thus from 0 to l (0 to 3 in your case).

Best,

Matteo

Il giorno sab 25 apr 2020 alle ore 06:18 Christoph Wolf
 ha scritto:

> Dear all,
>
> Does anyone know where to find the orbital order for the occupation matrix
> in PWSCF's Hubbard U for l=3? for l=2 I can see the orders on the manual
> for projwfc.x but I was unable to find it for the f-electrons!
>
> Best,
> Chris
>
> --
> Postdoctoral Researcher
> Center for Quantum Nanoscience, Institute for Basic Science
> Ewha Womans University, Seoul, South Korea
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Hubbard Correction

[Matteo Cococcioni]

Dear Fariba,
you need also inter-site interactions.

J. Phys.: Condens. Matter 22 (2010) 055602

The current implementation does not have this feature but DFT+U+V will be
in the code in the near future.



Il giorno dom 29 mar 2020 alle ore 08:52 Fariba Islam  ha
scritto:

> Dear everyone,
> Can I use Hubbard correction to find the correct bandgap of Silicon?
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Matteo Cococcioni
Department of Physics
University of Pavia
Via Bassi 6, I-27100 Pavia, Italy
tel +39-0382-987485, fax +39-0382-987752
e-mail matteo.cococci...@unipv.it 
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] LDA+U+V inclusion of Hubbard U term on f and d electrons simultaneously

[Matteo Cococcioni]

Dear William,

the DFT+U+V code is not yet public. We have had some technical difficulties
in porting it to the distributed version of QE so we haven't been able to
complete the task yet. We will work on this in the near future.
Best regards,

Matteo


Il giorno lun 9 dic 2019 alle ore 04:22 William Hewett <
williamholmeshewe...@gmail.com> ha scritto:

> Hi QE users,
>
>
>
> I’m working on some calculations on rare earth systems, specifically rare
> earth nitrides. The most successful calculations so far have been using the
> LDA+U+V method (applying different U corrections on f and d channels on the
> same atomic species simultaneously). As far as I can tell this is not
> possible currently in QE without manually editing the code.
>
> I’ve investigated this a bit and found forum posts going back to 2014
> asking the same question, with the answer that LDA+U+V it should be
> ‘available soon’.
>
> https://lists.quantum-espresso.org/pipermail/users/2014-June/029818.html
>
> I’ve also had a dig around in the code and found various references to the
> 'Hubbard_V' parameter specifically in hp_summary.f90 which are commented
> out.
>
> There also are various group who have achieved LDA+U+V in QE I guess by
> editing the code themselves.
>
> J. Phys.: Condens. Matter 22 (2010) 055602
>
> Computational Materials Science 95 (2014) 263–270
>
>
>
> Does anyone have an idea of when LDA+U+V may be available in the stable
> release of QE? Or can anyone offer some guidance on manually editing the
> code to make this possible?
>
>
>
> Kind regards
>
>
>
> Will Hewett
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] DFT + U not working on Sn 4d

[Matteo Cococcioni]

In addition to what Ari wrote, are you sure you are using the same settings
in the two calculations? Why are PAW-related terms of the energy zero when
using +U?
The Hubbard energy is very little. that is probably related to the fact
that Sn is d10. Are you sure you are doing what other people are doing in
literature?

Best,

Matteo

Il giorno dom 3 nov 2019 alle ore 08:54 후신 부지드  ha scritto:

> Hello,
>
> As indicated in the literature (for example
> https://www.sciencedirect.com/science/article/pii/S0927025616300672)
> people apply a Hubbard potential around 8 or 9 eV to correct the band gap
> of pure SnS2 from around 1.3 eV with only GGA to around 2 eV after applying
> U.
>
> Knowing that Sn d orbital is closed shell orbital (d10), I applied U of 9
> eV but band gap is not changing unlike what is reported in the literature,
> is it because it is closed shell, if so why it worked for other people ?
>
> I'm attaching the result of the calculation with and without U, and the
> density of states for both which look the same.
>
> Best
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Hubbard paramaters calculation with HP module

[Matteo Cococcioni]

Dear Caterina,

they are Bloch sums of atomic orbitals.

Best,

Matteo

Il giorno mer 11 set 2019 alle ore 15:49 MARIA CATERINA CEVALLOS BRENES <
maria.ceval...@ucr.ac.cr> ha scritto:

> Dear QE community:
>
> I just have one question regarding DFPT. What are the localized orbitals
> onto which KS-wavefunctions are projected? Are them Wannier functions?
>
> Kind regards,
>
> Caterina.
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] limit to take U value for DFT+U calculation

[Matteo Cococcioni]

Dear Rohit,

you could compute the value of U, for example using the linear-response,
DFPT-based hp.x code now included in QE. In the directory HP you will find
several examples on how to do that. Details about the implementation can be
found in PRB 98, 085127 (2018), arXiv:1805.01805v1 and references quoted
therein.

Best regards,

Matteo


Il giorno ven 6 set 2019 alle ore 07:53 ROHIT DAHULE 18210068 <
rohit.dah...@iitgn.ac.in> ha scritto:

> Dear Q-E users
> I m trying to get the band gap for System Cu2SnS3 with DFT + U.
> I have done calculation PBE + U by Considering U = 4, 5 , 6 , 7, 9  upto
> 15 and with increasing U values, band gap for the system also  increases.
> Is there any specific limit for consideration of U value ?
>
>
> Input file
>
> ---
> &CONTROL
>title = 'CTS'
>  calculation = 'scf'
> restart_mode = 'from_scratch'
>   outdir = './scratch'
>   pseudo_dir = './'
>   prefix = 'CTS'
>verbosity = 'high'
>nstep = 1000
> /
> &SYSTEM
>ibrav = 0
>  nat = 12
> ntyp = 3
>  ecutwfc = 80
>  ecutrho = 640
>  lda_plus_u = .TRUE.
> lda_plus_u_kind = 0
> Hubbard_U(1) = 15
> /
> &ELECTRONS
> electron_maxstep = 100
>  mixing_mode = 'plain'
>  mixing_beta = 0.4
>  mixing_ndim = 8
>  diagonalization = 'cg'
> /
> &IONS
> ion_dynamics = 'bfgs'
> /
> &CELL
>cell_dynamics = 'bfgs'
> /
> ATOMIC_SPECIES
>Cu   63.546000  Cu.pbe-dn-kjpaw_psl.1.0.0.UPF
>Sn  118.71  Sn.pbe-dn-kjpaw_psl.1.0.0.UPF
> S   32.065000  S.pbe-n-kjpaw_psl.1.0.0.UPF
>
> ATOMIC_POSITIONS {crystal}
> Cu   0.609860025   0.554603242   0.014502826
> Cu   0.756853280   0.738042423   0.513837567
> Cu   0.445393448   0.390139697   0.514502899
> Cu   0.261956405   0.243147538   0.013839616
> Sn   0.090842876   0.093003410   0.494452226
> Sn   0.906995789   0.909160925   0.994450414
> S0.060036047   0.768130605   0.387963060
> S0.231871856   0.939963608   0.887965000
> S0.886684205   0.601038738   0.879478677
> S0.398964467   0.113313382   0.379479276
> S0.537436346   0.292294346   0.880764475
> S0.707707256   0.462560085   0.380765964
>
> K_POINTS {automatic}
> 5 5 5  0 0 0
> CELL_PARAMETERS {bohr}
>   12.820803911   0.000373966   0.017355449
>6.411463480  11.102558326  -0.017368345
>   -2.152496468   3.728515202  12.101963487
>
> --
>
>
> Regards
> Rohit Dahule
>
>
> --
> Rohit Dahule
> M. Tech. Student
> Materials Science and Engineering
> IIT Gandhinagar
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] LDA+U+V functional in PWSCF

[Matteo Cococcioni]

Dear Chris,

I have been working on that, but didn't manage to complete the porting of
u+v into the public version. I will probably resume working on that soon
after  the summer break. Hopefully i will manage to finish the job next
time.
Best regards,

Matteo

Il dom 4 ago 2019, 11:07 Christoph Wolf  ha
scritto:

> Dear all,
>
> after reading the works of Prof. Cococcioni regarding the "on-site" U and
> "inter-site" V correction to DFT I was wondering if this was actually
> implemented in PWSCF and is undocumented or if this was never implemented
> in the public version?
>
> Any pointers in the right direction are very welcome!
>
> Best,
> Chris
>
> --
> Postdoctoral Researcher
> Center for Quantum Nanoscience, Institute for Basic Science
> Ewha Womans University, Seoul, South Korea
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Relaxation of Fe2O3

[Matteo Cococcioni]

Dear Anuja,

I don't have experience with this system and don't know how big the total
energy is. however, your convergence threshold for electrons (1.d-6) looks
a bit loose. that might result in not so accurate forces and, as a result,
ionic/cell steps are taken in the wrong direction. Try to tighten this
threshold. Also you may want to try to reduce the trust radius of the ionic
steps so the initial updates of ionic positions are not too big.
I assume you have studied the convergence wrt all the other parameters. Are
you sure, though, that a 888 k-point mesh is enough with such a small
Fermi-Dirac smearing of the distribution function? is the system metallic
in this phase?

Best regards,

Matteo



Il giorno dom 28 lug 2019 alle ore 18:08 Anuja Chanana <
anujachanan...@gmail.com> ha scritto:

> Dear users,
> I am trying to relax the bulk structure of alpha-Fe2O3 in the rhombohedral
> crystal structure. The ground state is +--+. However, the crystal lattice
> doesn't relax and the total energy values keep fluctuating rather than
> showing any convergence. The following is the input file
>
> &CONTROL
> calculation = 'vc-relax',
> restart_mode = 'from_scratch',
> title = 'Fe2O3',
> prefix = 'Fe2O3',
> outdir = './tmp_Fe2O3_rhom_scf_1',
> pseudo_dir = '.',
> forc_conv_thr = 1.0D-5,
> tprnfor = .true.,
> tstress = .true.
> verbosity = 'high'
> wf_collect = .true.,
> nstep = 1000,
> /
>
> &SYSTEM
>   ibrav=5,
>   celldm(1)=10.2528224724d0, celldm(4)=0.5694631780d0,
>   nat=10,
>   ntyp=5,
>   ecutwfc = 80,
>   ecutrho = 640,
>   occupations='smearing'
>   smearing='fd'
>   degauss= 0.005,
>   nspin=2,
>   starting_magnetization(1)= 0.0,
>   starting_magnetization(2) =  1.0,
>  starting_magnetization(3) =  -1.0,
>  starting_magnetization(4) =  -1.0,
>  starting_magnetization(5) =   1.0,
>   lda_plus_u = .true.
>   Hubbard_U(2) = 3.8
>   Hubbard_U(3) = 3.8
>   Hubbard_U(4) = 3.8
>   Hubbard_U(5) = 3.8
> /
>
> &ELECTRONS
> mixing_beta = 0.2,
> conv_thr = 1.0D-6,
> electron_maxstep=1000,
> /
>  &ions
>  /
>
>  &cell
> /
>
> ATOMIC_SPECIES
>   O 15.999400d0 O.pw91-n-rrkjus_psl.1.0.0.UPF
>   Fe1 55.845000d0 Fe.pw91-spn-rrkjus_psl.1.0.0.UPF
>   Fe2 55.845000d0 Fe.pw91-spn-rrkjus_psl.1.0.0.UPF
>   Fe3 55.845000d0 Fe.pw91-spn-rrkjus_psl.1.0.0.UPF
>   Fe4 55.845000d0 Fe.pw91-spn-rrkjus_psl.1.0.0.UPF
>
> ATOMIC_POSITIONS {crystal}
>O   0.9444650930d0   0.5556659533d0   0.2500659533d0
>O   0.2500650930d0   0.9444659533d0   0.5556659533d0
>O   0.0557952789d0   0.4445978598d0   0.7501978598d0
>O   0.4445952789d0   0.7501978598d0   0.0557978598d0
>O   0.5556650930d0   0.2500659533d0   0.9444659533d0
>O   0.7501952789d0   0.0557978598d0   0.4445978598d0
>   Fe1   0.1446976654d0   0.1446981632d0   0.1446981632d0
>   Fe2   0.6448278513d0   0.6448300697d0   0.6448300697d0
>   Fe3   0.3554325205d0   0.3554337433d0   0.3554337433d0
>   Fe4   0.8555627065d0   0.8555656499d0   0.8555656499d0
>
> K_POINTS {automatic}
>   8 8 8 0 0 0
>
>
> Has anyone ever tried relaxing the structure before and faced a similar
> situation?
> What is the best possible solution if the system doesn't show a smooth
> convergence.
> Looking forward to a reply.
>
> Thanks and Regards
> Anuja Chanana
>
>
>
> [image: Mailtrack]
> 
>  Sender
> notified by
> Mailtrack
> 
>  07/28/19,
> 09:35:20 PM
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Enquiry about the Error with both Spin Orbit Coupling and LDA+U included

[Matteo Cococcioni]

Dear Kieran,

no, this means that you cannot compute forces (nr stresses, I suppose) with
LDA+U and non-collinear magnetism. You can still run the calculation and
get the total energy and other quantities pertaining to the ground state.
But you cannot do structural optimization.

Best regards,

Matteo

Il giorno dom 7 lug 2019 alle ore 15:01 Kenan Song 
ha scritto:

> Dear All,
>
> I would like to make an enquiry. My system is antiferromagnetic and the
> spin orbit coupling coupling effect is quite strong. Furthermore, I also
> have *d*-shell electrons inside the system.
>
> Therefore, I need to use LDA+U correction on the *d* electron in the
> non-collinear calculation and set up the magnetism for the system. However,
> Quantum Espresso code responded to me with an error message below.
>
>
> %%
>  Error in routine force_hub (1):
>   forces in full LDA+U scheme are not yet implemented
>
>  
> %%
>
> Does it mean that Quantum Espresso code cannot work with both spin orbit
> coupling and LDA+U included case?
>
> Any answer would be appreciated.
>
> Kind regards,
>
> Kieran
>
> --
> This message and its contents, including attachments are intended solely
> for the original recipient. If you are not the intended recipient or have
> received this message in error, please notify me immediately and delete
> this message from your computer system. Any unauthorized use or
> distribution is prohibited. Please consider the environment before printing
> this email.___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] Charges on dopants

[Matteo Cococcioni]

Dear Eric,

just a couple of quick comments.
If you are already using a large supercell you can probably avoid
supercells (all this would need to be checked to be sure).
Also keep in mind that from version 6.4.1 you can find in the QE
distribution a code called HP (Hubbard parameters) that computes Hubbard U
automatically using DFPT. More details here:
10.1103/PhysRevB.98.085127.
Hope this helps.
Best regards,

Matteo


Il giorno mer 26 giu 2019 alle ore 21:51 Eric Glen Suter 
ha scritto:

> Hello all,
>
>
> I'm trying to simulate transition metal dopants in particular charge
> states. I'm more or less familiar with the "tot_charge" tag and how it
> functions. For these transition metals, it seems the extra charge I
> introduce doesn't want to localize on my dopants. I've been looking into
> using the Hubbard U as a way to coerce this extra electron (or hole in some
> cases) to localize on my dopant. I've read up a bit on the literature
> about these types of corrections, but I'd like to know:
>
>
> 1) Am I on the right track with this line of reasoning? I also take notice
> of the "starting_charge" tag for pw.x. I haven't tried it out, but is that
> a viable way of trying to coax the extra charge to stay on the dopant?
>
>
> 2) If Hubbard U really is the way to go, is there a way of tuning the U
> parameter that doesn't involve supercells? I'm already working with a
> pretty large cell and I don't have a ton of computational power at my
> disposal.
>
>
> I understand this is no trivial task, but if anyone has any insight on how
> to model a dopant in a particular charge state, I'd be grateful for a nudge
> in the right direction.
>
>
> Thank you in advance for any help you might have to offer,
>
> Eric Suter
>
> Dept. of Physics and Astronomy
>
> University of Georgia
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [Pw_forum] total energy in DFT+U

[Matteo Cococcioni]

Dear Farah,

first of all: total energies are always defined up to a constant. if
anything, you should be looking at energy differences (e.g. between
different crystal structures or magnetic orderings if that applies to your
case) rather than total energies per se. Also, your expectation is not
right: the DFT+U total energy (as usually written) is not variational with
respect to U. That is why (or one of the reasons why) typically you need
linear-response calculations to compute it (PRB 71, 035105) rather than a
trivial minimization of the energy.

Best regards,

Matteo



On Thu, Jun 8, 2017 at 9:34 AM, FARAH MARSUSI  wrote:

> Dear all,
>
> I have done DFT+U calculations in a semi-empirical way by increasing U
> parameter until the magnetic moment (M) equal to experimental value was
> obtained along with a phase transition from metal to insulator, as seen in
> experiment. All physical findings are reasonable, except total energies. By
> increasing U and reaching to experimental M, total energy is increasing
> too. I expected the lowest total energy for it!
>
>
> Best regards,
>
> F. Marsusi,
>
> Department of Physics,
> Amirkabir University of Technology.​
>
> --
> This email was Anti Virus checked by  Security Gateway.
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Error during DFT+U calculation using pw.x

[Matteo Cococcioni]

Dear Sai,

try to double-check the changes you did in those routines. If they were
consistent with what it was already in there it should work.

Of course you need to recompile the code after updating the routines.

Best,

Matteo

On Fri, May 12, 2017 at 11:54 AM, Sai Phani  wrote:

> Dear all,
> I am trying to perform DFT+U calculation for pure lithium ion but the
> calculation is getting stopped within few seconds after the submission with
> the following error message in the CRASH file,
>
>
>   
> %%
>  task # 6
>  from set_hubbard_l : error # 1
>  pseudopotential not yet inserted
>  %%%
> %%%
>
>
>  %%%
> %%%
>  task # 9
>  from set_hubbard_l : error # 1
>  pseudopotential not yet inserted
>  %%%
> %%%
>
>
>  %%%
> %%%
>  task # 5
>  from set_hubbard_l : error # 1
>  pseudopotential not yet inserted
>  %%%
> %%%
>
> I had gone through the previous FAQ's and it was mentioned that the
> "angular momentum" and the "approximate occupation" in *set_hubbard_l.f90*
> and *tabd.f90* files.
> I had set the values of hubbard_l = 1 and 2 in *set_hubbard_l.f90* and
> hubbard_occ = 1.d0 in *tabd.f90 *but still the problem persists.
>
> Could anyone of you suggest me the way of rectifying this problem to run
> it successfully.
>
>
>
>
> Thanks & Regards,
> Sai Phani Kumar. V,
> Research Scholar (PhD),
> Quantum and Molecular Engineering Laboratory,
> Department of Chemical Engineering,
> Indian Institute of Technology Kharagpur,
> India-721302.
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] convergence can't achieved with QE6.0.2 and 5.4.0

[Matteo Cococcioni]

I'm pretty sure forces and stresses were tested in all +U flavors, at least
for the version of the code where they were originally implemented.
It is true that +U typically leads to the creation of several local minima
and maybe this makes the convergence harder. However, I have never seen
a total force staying so constant (and big) as you show. Are the ions
moving at all? How big is your trust radius?
Does the relaxation converge if you set Hubbard_J0 = 0?
Also, is "exxdiv_treatment = 'gygi-baldereschi' " needed?

Matteo


On Fri, May 5, 2017 at 10:37 AM, Lorenzo Paulatto <
lorenzo.paula...@impmc.upmc.fr> wrote:

> On Friday, 5 May 2017 09:26:53 CEST Q.J.Wang wrote:
> >  lda_plus_u_kind = 0 ,
> > Hubbard_U(3) = 4.5,
> >Hubbard_J0(3) = 0.5,
> >...
> > The total force seems nearly invariable. I also use QE5.4.0 to run the
> input
> > file, the total force still can't  converge after 300 scf cycles and  2
> bfgs
> > steps.
>
> My guess is that there is an inconsistency between LDA+U energy and forces,
> which prevents the BFGS calculation from converging.
>
> kind regards
>
> --
> Dr. Lorenzo Paulatto
> IdR @ IMPMC -- CNRS & Université Paris 6
> phone: +33 (0)1 442 79822 / skype: paulatz
> www:   http://www-int.impmc.upmc.fr/~paulatto/
> mail:  23-24/423 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] nscf run of GGA+U

[Matteo Cococcioni]

The error message says that the code could not read the "ns" (the atomic
occupations). Couldn't it be that for some reason the file that contains
them in the temp directory got erased between scf and nscf?

On Wed, Mar 1, 2017 at 11:06 AM, Paolo Giannozzi 
wrote:

> Hard to say. It might depend upon the way the code is run. I run it
> serially or  in parallel on a single processor, but maybe there is a
> problem with more processors. Or maybe there is no problem in the code
> but in the way it is compiled.
>
> Paolo
>
> On Wed, Mar 1, 2017 at 10:13 AM, rezvan molavi 
> wrote:
> > Dear paolo
> >
> > but  this is my nscf out put :
> >
> > Error in rutine  read-rho-general
> > reading ldaU ns
> >
> > may it be a problem of my computer?
> >
> > regards
> >
> > On Wed, Mar 1, 2017 at 12:16 PM, Paolo Giannozzi 
> > wrote:
> >>
> >> ... and here what you get on output.
> >>
> >> On Tue, Feb 28, 2017 at 10:28 PM, project way 
> >> wrote:
> >> > here are scf and nscf codes
> >> >
> >> > regards
> >> >
> >> > On Tue, Feb 28, 2017 at 8:25 PM, project way  >
> >> > wrote:
> >> >>
> >> >> On 2/28/17, project way  wrote:
> >> >> > Hello
> >> >> > Dear QE developers and users
> >> >> >
> >> >> > Im using QE-5.3.0 on ubuntu. I have been running my code using
> GGA+U
> >> >> > and I used the U values of an article.  the scf calculation was
> done
> >> >> > without any problem but just in nscf calculations it seems that
> nscf
> >> >> > program can not read U values and the following error was appeared:
> >> >> >
> >> >> > Error in routine read_rho_general (1):
> >> >> >  Reading ldaU ns
> >> >> >
> >> >> > thanks everyone who can help.
> >> >> >
> >> >
> >> >
> >> >
> >> > ___
> >> > Pw_forum mailing list
> >> > Pw_forum@pwscf.org
> >> > http://pwscf.org/mailman/listinfo/pw_forum
> >>
> >>
> >>
> >> --
> >> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> >> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> >> Phone +39-0432-558216, fax +39-0432-558222
> >>
> >> ___
> >> Pw_forum mailing list
> >> Pw_forum@pwscf.org
> >> http://pwscf.org/mailman/listinfo/pw_forum
> >
> >
> >
> > ___
> > Pw_forum mailing list
> > Pw_forum@pwscf.org
> > http://pwscf.org/mailman/listinfo/pw_forum
>
>
>
> --
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] problem with DFT+U

[Matteo Cococcioni]

Dear Hongshen,

I don't have a clear idea of what could be causing your problem. I would
try anyway to move to the latest version of the code. Maybe the problem got
solved in between the two.

Best regards,

Matteo



On Thu, Feb 9, 2017 at 12:32 PM, Hongsheng Liu 
wrote:

> Dear Matteo,
>   Thank you for your reply. I'm sorry for the unclarity of my problem. It
> can work when lda_plus_u = .false.. I'm using PWSCF v.5.4.0. The error
> always appears after some steps of scf (before convergency), before the
> calculation of forces and stresses.
>
> Best regards,
> Hongsheng
>
> 2017-02-09 9:54 GMT+01:00 Matteo Cococcioni :
>
>> Dear  Hongshen,
>>
>> does it work when lda_plus_u = .false.? from your email it is not clear
>> whether the error is due to the +U part or not. also, are you using the
>> latest version of the code or an older one? at what point of the
>> calculation does the error appear? is it in the calculation of forces,
>> stresses or before?
>>
>> Matteo
>>
>>
>> On Wed, Feb 8, 2017 at 5:49 PM, Hongsheng Liu 
>> wrote:
>>
>>> Dear all,
>>>   I'm trying to do a geometry optimization for bulk magnetite with
>>> PBE+U. The job succeeded with primitive cell (including 14 atoms), but
>>> failed with conventional cell (including 56 atoms). The error message is
>>> shown below,
>>>   'Fatal error in PMPI_Bcast: Other MPI error, error stack:
>>>   PMPI_Bcast(2434): MPI_Bcast(buf=0x998c5a0, count=3366,
>>> MPI_DOUBLE_PRECISION,   root=4, comm=0x8402) failed
>>>   MPIR_Bcast_impl(1807)...:
>>>   MPIR_Bcast(1835):'
>>>
>>> Similar question was asked before on pw_forum, but it seems no solution
>>> till now.
>>>  My input is listed below,
>>>  &CONTROL
>>>   calculation= "vc-relax",
>>> ..
>>> /
>>> &SYSTEM
>>>   ibrav = 1
>>>   A = 8.522631
>>>   nat = 56,
>>>   ntyp = 3,
>>>   ecutwfc = 42.0,
>>>   ecutrho = 340.0,
>>>   nspin = 2,
>>>   starting_magnetization(1) = 0,
>>>   starting_magnetization(2) = -0.25,
>>>   starting_magnetization(3) = 0.25,
>>>   occupations = 'smearing',
>>>   smearing = 'gaussian',
>>>   degauss = 0.0008,
>>>   lda_plus_u = .TRUE.
>>>   lda_plus_u_kind = 0
>>>   Hubbard_U(1) = 0,
>>>   Hubbard_U(2) = 3,
>>>   Hubbard_U(3) = 3,
>>> /
>>> .
>>> /
>>> &CELL
>>>   cell_dofree = 'volume'
>>> /
>>> ..
>>> K_POINTS automatic
>>> 6 6 6 0 0 0
>>>
>>> I appreciate any help!
>>>
>>> ___
>>> Pw_forum mailing list
>>> Pw_forum@pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>
>>
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum@pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] problem with DFT+U

[Matteo Cococcioni]

Dear  Hongshen,

does it work when lda_plus_u = .false.? from your email it is not clear
whether the error is due to the +U part or not. also, are you using the
latest version of the code or an older one? at what point of the
calculation does the error appear? is it in the calculation of forces,
stresses or before?

Matteo


On Wed, Feb 8, 2017 at 5:49 PM, Hongsheng Liu 
wrote:

> Dear all,
>   I'm trying to do a geometry optimization for bulk magnetite with PBE+U.
> The job succeeded with primitive cell (including 14 atoms), but failed with
> conventional cell (including 56 atoms). The error message is shown below,
>   'Fatal error in PMPI_Bcast: Other MPI error, error stack:
>   PMPI_Bcast(2434): MPI_Bcast(buf=0x998c5a0, count=3366,
> MPI_DOUBLE_PRECISION,   root=4, comm=0x8402) failed
>   MPIR_Bcast_impl(1807)...:
>   MPIR_Bcast(1835):'
>
> Similar question was asked before on pw_forum, but it seems no solution
> till now.
>  My input is listed below,
>  &CONTROL
>   calculation= "vc-relax",
> ..
> /
> &SYSTEM
>   ibrav = 1
>   A = 8.522631
>   nat = 56,
>   ntyp = 3,
>   ecutwfc = 42.0,
>   ecutrho = 340.0,
>   nspin = 2,
>   starting_magnetization(1) = 0,
>   starting_magnetization(2) = -0.25,
>   starting_magnetization(3) = 0.25,
>   occupations = 'smearing',
>   smearing = 'gaussian',
>   degauss = 0.0008,
>   lda_plus_u = .TRUE.
>   lda_plus_u_kind = 0
>   Hubbard_U(1) = 0,
>   Hubbard_U(2) = 3,
>   Hubbard_U(3) = 3,
> /
> .
> /
> &CELL
>   cell_dofree = 'volume'
> /
> ..
> K_POINTS automatic
> 6 6 6 0 0 0
>
> I appreciate any help!
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] How to apply DFT+U method for specific orbitals

[Matteo Cococcioni]

Dear Meysan,

what atomic states the Hubbard correction is applied to can be controlled
"by hand". Give a look to set_hubbard_n.f90 and set_hubbard_l.f90 in the
Modules directory of the QE distribution. The content is quite
self-explanatory. Of course you need to recompile if you change something
in any of these routines.

Hope this helps.

Matteo

On Tue, Jan 3, 2017 at 1:33 PM, meysam pazoki 
wrote:

> Dear All
> Hi!
>
> Here i have a question regarding the LDA+U method that i couldnt find in
> the pw.x help file,
> I appreciate if you can assist me for that:
>
> I am calculating a lanthanide oxide using GGA+U method , i want to apply U
> and J Hubbard values just to f electrons and not to the d electrons.
> I couldnt find any keyword in pw.x that i can apply the Hubbard parameters
> to specific orbitals, i can just set some values however i dont know the
> would be considered for which orbitals.
>
> Can you please clarify for me how to apply U and J Hubbard values just to
> f electrons and not to the d electrons. ?
>
> and also how pw.x apply the Hubbard parameters to different orbitals? Does
> it just choose the highest orbital or ..?
>
> Thanks in advance
> Meysam Pazoki
> Researcher, Chemistry Department
> Uppsala Univerity
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] A Cutting-edge Question !!!

[Matteo Cococcioni]

Dear Ashkan,

I'm not sure I understand your question completely, but will attempt an
answer.

First thing to keep in mind is that QE (as any other DFT code) works with
the Kohn-Sham single particle Hamiltonian (is that what you are looking
for?), whose eigenstates are the ones that allow you to construct the
ground state charge density of a system and to evaluate its total energy.
Due to the Bloch theorem (i.e. to the translational invariance of
crystalline solids) this Hamiltonian is block-diagonal on the k-points
(crystal momentum of electrons). Also, QE uses an expansion of Kohn-Sham
wavefunctions on a plane-wave basis set. So, each of these blocks of the
Hamiltonian is npw x npw where npw is the number of plane-waves used in the
expansion of the wavefunctions of that specific k-point. QE performs an
iterative diagonalization of each block that is involves computing the
action of the Hamiltonian onto the current wavefunction H |psi>. This is
done in a routine called h_psi which is the driver to compute various parts
of the Hamiltonian and to operate it on the wavefunction. So I guess you
can look inside that routine in order to find what you need.

Best regards,

Matteo

On Sun, Nov 13, 2016 at 11:24 PM, ashkan shekaari 
wrote:

> Dear experts,
>
> How, could one derive the Hamiltonian of a given system resulting in
> energy eigenvalues (band structure) *through the modules or subroutines*
> included in Q. E. integrated suite?
>
> Is there anyway for this end?
>
> For example, if I provide an input scf file, how could I figure out what
> Hamiltonian will be used in my calculations?
>
> How could I make a change in the Hamiltonian of a system by manipulating
> subroutines (not the input file)?
>
>
> *--*
> *Regards,*
> *Ashkan Shekaari*
> *Plasma Physics Research Center*
> *Science and Research Branch*
> *I A U, 14778-93855 Tehran, Iran.*
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Assigning Hubbard potential to f orbitals

[Matteo Cococcioni]

Dear Mohammed,

you may find the tutorial on DFT+U contained in this page useful:

http://www.iiserpune.ac.in/~smr2626/talks-presentations.html

Best,

Matteo

On Sun, Oct 23, 2016 at 8:25 AM, Mohammed Khalafalla 
wrote:

> Dear all,
> Please kindly let me know how to Assign Hubbard potential to f orbital in
> LDA+U calculation using quantum espresso.
> Regards,
> Mohammed Khalafalla
> Taibah University
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] lda+U abinitio U

[Matteo Cococcioni]

Hi Lorenzo,

the two tutorial should be quite equivalent, although the one Federico
found is more recent and probably I updated some details.

Regarding your questions: as far as I understand you are only interested in
U on one specific atomic species of your materials. You could do that by
doing two perturbations: one on the atom you are interested in, the second
on all the other atoms (which you treat as a "macro-atom") at the same
time. Of course the occupation of this second "extended atom" is the sum of
the occupations of the atoms it is composed by. you then construct a 2x2
response matrix that, once inverted, should give you the U you are looking
for (throwing away the one for the "macro-atom").
This only limits the number of perturbation but still requires a supercell
of sufficiently large size.

We are working on a way to make the whole procedure more efficient, through
automatizing the linear-response, but the code is not ready yet.

Best,

Matteo

On Fri, Sep 2, 2016 at 5:55 PM, Lorenzo Paulatto <
lorenzo.paula...@impmc.upmc.fr> wrote:

> Hello,
> I have a question about how to compute the abinitio U, I'm following the
> online Santa Barbara 2009 tutorial (and trying to use the script therein)
> and
> PRB 71, 35105 (2005).
>
> I have a system that is not very large but quite heavy to compute, and have
> several atomic species (3 at first, then 4) but only one is problematic,
> as it
> is could be Cerium or other Lanthanoids.
>
> It would be quite anoying and very cpu time consuming for me to properly*
> compute U by finite response for all the species, but I'm not sure that
> 1. it is possible with the available toolchain
> 2. it makes sense
>
> Also, if somebody (e.g. Matteo) has some more recent and/or more user
> friendly
> code to compute dalpha/dn I'm a taker.
>
> thank you for your help!
>
> *) by properly I mean take care that it is converged with the supercell
> size
>
> --
> Dr. Lorenzo Paulatto
> IdR @ IMPMC -- CNRS & Université Paris 6
> +33 (0)1 44 275 084 / skype: paulatz
> http://www.impmc.upmc.fr/~paulatto/
> 23-24/4é16 Boîte courrier 115,
> 4 place Jussieu 75252 Paris Cédex 05
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Subject: Relaxing a 2x2x2 supercell ...while reading input file getting "wrong number of columns in Atomic positions error" for silver atom created from Xcrysden

[Matteo Cococcioni]

open your input file and check the atomic positions. there is something
wrong there. maybe you forgot to specify the atomic species, or something
else the code expects to find. I typically get this error when I fail to
append the file with positions. I'm not sure this is the error you get if
you indicate a wrong number of atoms. check that too.

hope this helps.

Matteo

On Thu, Jul 21, 2016 at 9:03 AM, Md Mahabul Islam 
wrote:

> Hi pwscf users & developers,
> I am trying to relax a silver atom with vacancy but while reading the
> input file I am getting  "wrong number of columns in Atomic positions
> error".The atomic positions were created from Xcrysden for 2x2x2 supercell
> (asymmetric unit).
> Any help regarding this will be highly appreciated.
> Thank you,
> *Md Mahabul Islam*
> *PhD Candidate*
>
> *Department of Physics,*
>
>
> *Indian Institute of Technology Madras,Chennai-600036, India*Mobile- +91
> 9087297118/+91-9593148106
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] set_hubbard_l.f90 and tabd.f90 files

[Matteo Cococcioni]

If things didn't change in the last releases (I have not checked)
set_hubbard_l is in flib while tabd is in PW/src/.

Best,

Matteo



On Sat, Jul 16, 2016 at 1:15 PM, Winfred Mulwa 
wrote:

> Dear all,
> I want to check if Ti is in the list of known atoms for the  +u functional.
> Can anyone advise me on where the above named files are located in the
> current espresso distribution.
> Regards
> Mulwa Winfred.
> D Phil Student, Computational Material Science Group,
> University of the Free State - QwaQwa,
> South Africa.
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] ACBN0 pseudopotentil - regarding

[Matteo Cococcioni]

Dear Varma

you may have to ask the authors of the paper for a more consistent help. As
far as I know/understand from the paper you mention, the ACBN0 is a method
to compute the value of the Hubbard U (based on an ancillary calculation
performed on a gaussian basis set) but does not modifies the
pseudopotential. So I guess it can work with any kind of PP (just like the
normal LDA+U does, independently on how you choose U). However, the value
of U has to be determined with the same PP you plan to use it with, for a
good numerical consistency.

Regards,

Matteo

On Thu, Feb 4, 2016 at 6:43 AM, chaitanya varma  wrote:

> Respected Sir,
> I have seen in one paper Phys Rev X 5, 011006 (2015) that when ACBN0 pp is
> used for calculating band gap of ZnO with Hubbard U values UZn = 12.8eV and
> UO = 6.7eV, they got almost good value for band gap (2.91eV).
> I would like to know how to get ACBN0 pp for Mn, W and O for calculating
> electronic structure of MnWO4.
>
> Thank you
>
> regards
>
> Chaitanya Varma M
>  Assistant Professor
> Dept of Physics
> GIT
> GITAM University
> Visakhapatnam, India
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] forces in full LDA+U scheme are not yet implemented

[Matteo Cococcioni]

Dear Raj kamal,

I do not know much about the implementation of forces with the full LDA+U.
if your system could be treated well also with the simpler version LDA+U,
using lda_plus_u_kind = 0 and maybe a finite Hubbard_J0, forces (and
stresses) are implemented for this case.

Best regards,

Matteo

On Sat, Jan 23, 2016 at 10:38 AM, Raj kamal 
wrote:

> dear QE experts
>i trying to relax Limnsio4 structure with GGA + U. it shows
> error ,,from force_hub : error # 1
>   forces in full LDA+U scheme are not yet implemented. please help me
> to solve this problem.thanks in advance.
>
>
> this is my input.
>
> &CONTROL
>  calculation = 'relax' ,
>   outdir = '/home/kathirvel/espresso/tmp/' ,
>   pseudo_dir = '/home/kathirvel/espresso/pseudo/' ,
>   prefix = 'Limnsio4' ,
>etot_conv_thr = 1.0D-3 ,
>forc_conv_thr = 1.0D-2 ,
>   tprnfor=.TRUE.
>  /
>  &SYSTEM
>   ibrav  = 8,
>A = 6.31850,
>B = 5.38650,
>C = 4.97540,
>cosBC = 0,
>cosAC = 0,
>cosAB = 0,
> nat  = 16,
>ntyp  = 4,
> ecutwfc  =30.0 ,
>   occupations='smearing',
>  smearing='mv',
>   degauss=0.01,
> lda_plus_u = .TRUE.
> lda_plus_u_kind=1
> Hubbard_U(3)= 6
> Hubbard_J(1,3)=1
>
>  /
>  &ELECTRONS
>  mixing_mode  = 'local-TF' ,
>  mixing_beta  = 0.7,
>  diagonalization  = 'david' ,
>  conv_thr = 1.0e-6,
>   /
>  &IONS
>  /
> ATOMIC_SPECIES
> Li  6.941 Li.pbe-n-van.UPF
> O   15.999O.pbe-rrkjus.UPF
> Mn  54.938Mn.pbe-sp-van.UPF
> Si  28.085Si.pbe-rrkj.UPF
> ATOMIC_POSITIONS angstrom
> Li   1.59321   1.76467   4.84987
>  O   1.35450   3.71566   4.40074
> Mn   3.15925   4.43040   4.87057
>  O   3.15925   0.82430   4.07092
> Si  -0.0   4.52261   4.90236
>  O  -0.0   0.70752   4.35596
> Li   1.56604   3.62183   2.36217
> Li   4.75246   3.62183   2.36217
> Li   4.72529   1.76467   4.84987
>  O   1.80475   1.67084   1.91304
>  O   4.51375   1.67084   1.91304
>  O   4.96400   3.71566   4.40074
> Mn  -0.0   0.95610   2.38287
>  O  -0.0   4.56220   1.58322
> Si   3.15925   0.86389   2.41466
>  O   3.15925   4.67898   1.86826
> K_POINTS automatic
>  5 5 5  0 0 0
>
>
> --
> *Best regards,*
> *Rajkamal.A.*
> *Research Scholar,(SRM UNIV).*
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] LDA+U+Phonons in QE 5.3.0

[Matteo Cococcioni]

Dear Paul,

yes, the implementation that allows DFPT calculations from a DFT+U ground
state is quite substantial (especially with US PPs). Unfortunately, we
could only work on this project intermittently for the past years, and the
progress has been slow. We are still working to improve the code and clear
some problems; it will be released in some form when we feel it is ready.

Matteo


On Sun, Jan 17, 2016 at 2:10 AM, W2AGZ  wrote:

> I just had a quick look at the source code, phq.readin.f90 in QE release
> 5.3.0, and see that support of lda_plus_u is still not supported for the
> calculation of electron-phonon interactions in Hubbard manifolds.  It’s
> been a number of years since this issue was originally posted on pw_forum.
> Is their a particular problem within the QE formalism, maybe in the basis
> set resulting from a Hubbard calculation, that would make this extremely
> difficult…or impossible…to implement?   What source code routines would
> need modification/replacement?
>
>
>
> Thanks, -Paul
>
>
>
> *Paul Michael Grant, PhD*
>
> *Physicist and Science Writer*
>
> *Senior Life Fellow, American Physical Society*
>
> *Fellow, Institute of Physics, United Kingdom*
>
> *APS Distinguished Lecturer on Applications of Physics (2014-15) *
>
> *Staff Associate, Jet Propulsion Laboratory, NASA (2011-15)*
>
> *Visiting Scholar, Applied Physics, Stanford (2005-2008)*
>
> *EPRI Science Fellow (Retired)*
>
> *IBM Research Staff Member/Manager Emeritus*
>
> *Principal, W2AGZ Technologies*
>
> *w2...@w2agz.com *
>
> *http://www.w2agz.com* 
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] filling the single state (A1g) in DFT+U calculation

[Matteo Cococcioni]

Dear Yusuf,

no, the filling of the A1g orbital is not a universal thing, just a trick
useful in FeO. It was added to the tutorial to show how to do that in case
you need.

hope this helps,

Matteo

On Tue, Oct 13, 2015 at 1:12 PM, Yusuf Zuntu  wrote:

> Dear QE Users,
>
> I have calculated U of my model based on linear response approach, but I
> am yet to understand whether filling up the single state (A1g) as proposed
> in the tutorials
>
> http://media.quantum-espresso.org/santa_barbara_2009_07/slides-exercices/Handson_ldau.pdf
>
> is universal for all systems. I have a system of boron nitride doped with
> transition metals. Without imposing state on the singlet, the (A1g) tends
> to have not the lowest state in the minority spin as seen below:
>
> relax calculations:
>
>  spin  1
> eigenvalues:
>   0.697  0.758  1.023  1.045  1.048
>
> spin  2
> eigenvalues:
>   0.021  0.023  0.042  0.110  0.118
>
> My question is do i have to fill up the singlet state as recommended in
> the tutorial or no need. Although I do not have any experimental results to
> define the say the expected final outcome of the result (whether is
> semi-conducting, insulator or metallic). I will equally need some physical
> evidence as to why the imposition of the state on the singlet state.
> Thank you
>
> Yusuf Zuntu
> PhD candidate
> USM
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] help for calculating Hubbard parameter

[Matteo Cococcioni]

Dear Forzad,

if you search the QE webpage (in the "resources" section, I believe) you
will find the notes and lectures from several past QE schools, workshops,
tutorials and there should be some about the calculation of U. One is in
the Santa Barbara school from 2009. A second one should be among the notes
from a school in Pune last year.

hope this will help you.

best regards,

Matteo



On Thu, Oct 8, 2015 at 12:11 PM, Farzad Molani  wrote:

> Dear QE users,
> I want to calculate Hubbard parameter. Has any body  a tutorial "step by
> step" for calculating the hubbard parameter? Is this input file correct?
> How can I use the output file?
>
>
> &CONTROL
>   calculation  ="scf",
>   pseudo_dir   = "./",
>   restart_mode = 'restart',
>   outdir   = "./",
>   prefix   = "geraphene-Fe-ldaU",
>   verbosity= 'high',
>   tprnfor   = .true.,
>   tstress   = .true.,
> /
> &SYSTEM
>   ibrav   = 4,
>   celldm(1)   = 9.282,
>   celldm(3)   = 2.035,
>   nat = 9,
>   ntyp= 2,
>   ecutwfc = 44.2,
>   ecutrho =300,
>   nspin   = 2,
>   starting_magnetization(1)=0.5,
>   starting_magnetization(2)=0.5,
>   occupations='smearing',
>   smearing   ='m-v',
>   degauss=0.003,
>   lda_plus_u = .true.
>   Hubbard_alpha(2)=-0.04,
> /
> &ELECTRONS
>   conv_thr  = 1.0d-10,
>   mixing_beta = 0.5d0,
>   diagonalization  = 'cg',
> /
> &IONS
> /
> &CELL
> /
> ATOMIC_SPECIES
> C   12.010   C.pz-rrkjus.UPF
> Fe  55.8452  Fe.pz-nd-rrkjus.UPF
> ATOMIC_POSITIONS {angstrom}
> C   -0.034035640   1.396956433   4.962804121
> C1.208811211   0.679456444   4.961853267
> C2.451565749   1.396929605   4.962300355
> C3.664662075   0.696596615   5.017209108
> C   -1.247079599   3.532441567   5.017139042
> C   -0.034018302   2.832082543   4.961775758
> C1.208707850   3.549535163   4.962481191
> C2.451470952   2.831954512   4.963586323
> Fe   1.207584375   2.113742807   6.427714456
> K_POINTS automatic
>  5 5 1 0 0 0
>
>
> Best regards
> Farzad Molani,
> Ph.D in Computational Chemistry
> Department of Chemistry,
> Islamic Azad University of Sanadaj
> Tel.: 009891 4442 3308
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] DFT+U

[Matteo Cococcioni]

On Thu, Oct 1, 2015 at 2:15 PM, paresh rout  wrote:

> Thank you sir for the reply . I was just confused how to use DFT+Ueff .
> Still I have some query  If I follow the first method for DFT+Ueff  (U-J)
> then isn't just like DFT+U method which will just use a small U=Ueff
> (Ueff=U-J) instead of large original U ? Then how will the code
> differentiate  DFT+U and DFT+Ueff ?
>


As you said, just from the value of U. Unless you use 2) or 3) from your
list.

Best,

Matteo



>
> Kind Regards
> Paresh
>
> On Wed, Sep 30, 2015 at 10:28 PM, Matteo Cococcioni 
> wrote:
>
>>
>> dear Paresh,
>>
>> for 2) the code does what is explained in PRB 84, 115108 (2011), which is
>> not Ueff = U-J
>>
>> if you need DFT+Ueff just use 1) with U = Ueff.
>>
>> Best,
>>
>> Matteo
>>
>> On Sat, Sep 26, 2015 at 8:58 AM, paresh rout 
>> wrote:
>>
>>> Dear all,
>>> I want to confirm DFT+U , DFT+Ueff and DFT+U+J method that quantum
>>> espresso uses . So far I understand
>>> 1- For simply DFT+U  calculation I have to use
>>> lda_plus_u=.true.
>>> lda_plus_u_kind=0
>>> Hubbard_U(i)=U value
>>> 2-For DFT+Ueff(where Ueff=U-J)
>>> lda_plus_u=.true.
>>> lda_plus_u_kind=0
>>> Hubbard_U(i)=U value
>>> Hubbard_J0(i)=J values
>>> 3-For DFT+U+J method
>>>lda_plus_u=.true.
>>>lda_plus_u_kind=1
>>>Hubbard_U(i)=U value
>>>Hubbard_J(i,ityp)=J values
>>> If the above ways are right then for DFT+Ueff case
>>> does the code will do Ueff=U-J ?
>>> Any help would be highly appreciated .
>>>
>>> Kind Regards
>>> Paresh Chandra Rout
>>> Research Scholar
>>> Indian Institute of Science Education and Research Bhopal
>>>
>>>
>>> ___
>>> Pw_forum mailing list
>>> Pw_forum@pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>
>>
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum@pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] DFT+U

[Matteo Cococcioni]

dear Paresh,

for 2) the code does what is explained in PRB 84, 115108 (2011), which is
not Ueff = U-J

if you need DFT+Ueff just use 1) with U = Ueff.

Best,

Matteo

On Sat, Sep 26, 2015 at 8:58 AM, paresh rout 
wrote:

> Dear all,
> I want to confirm DFT+U , DFT+Ueff and DFT+U+J method that quantum
> espresso uses . So far I understand
> 1- For simply DFT+U  calculation I have to use
> lda_plus_u=.true.
> lda_plus_u_kind=0
> Hubbard_U(i)=U value
> 2-For DFT+Ueff(where Ueff=U-J)
> lda_plus_u=.true.
> lda_plus_u_kind=0
> Hubbard_U(i)=U value
> Hubbard_J0(i)=J values
> 3-For DFT+U+J method
>lda_plus_u=.true.
>lda_plus_u_kind=1
>Hubbard_U(i)=U value
>Hubbard_J(i,ityp)=J values
> If the above ways are right then for DFT+Ueff case
> does the code will do Ueff=U-J ?
> Any help would be highly appreciated .
>
> Kind Regards
> Paresh Chandra Rout
> Research Scholar
> Indian Institute of Science Education and Research Bhopal
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] about hubbard_l and hubbard_occ of Magnesium

[Matteo Cococcioni]

Dear Muhammad,

you have to look inside the routines set_hubbard_l.f90 and tabd.f90 in
PW/src. Probably you need to add information about Mg (I am not sur eit is
listed).

Best,

Matteo

On Mon, Aug 17, 2015 at 4:53 PM, zafar rasheed 
wrote:

> Dear All
> I want to perform LDA+U calculations for magnesium(Mg (atomic No. 12 )).
> What will be the values for  hubbard_l and hubbard_occ of* Magnesium*
>
> Waiting for kind reply.
>
> Muhammad Zafar
> PhD Scholar
> Department of Physics
> The Islamia University of Bahawalpur,Pakistan
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] DFT+U+V

[Matteo Cococcioni]

Dear Vardha,

DFT+U+V is not yet available on the latest version of QE, but I'm working
to port it, so stay tuned on this same channel :-). Hopefully it won't take
too long.
If you compute U using PRB 0235105 (2005) you are also computing V (as
off-diagonal element of the interaction matrix). You can find all the
details in
 J. Phys.: Condens. Matter 22 055602 (2010)

Best,

Matteo


On Sat, Jun 6, 2015 at 10:48 AM, Varadharajan Srinivasan <
varadharajan.sriniva...@gmail.com> wrote:

> Dear all,
>
> I was wondering if DFT+U+V option is available in the latest versions of
> QE? I am testing this on some covalent systems. Also, is it possible to
> calculate the V from linear response just like the U? If so, could anyone
> point me to a good reference?
>
> Thanks,
> Vardha.
>
> Asst. Prof., Chemistry
> IISER Bhopal
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Problem with determination of U using linear response

[Matteo Cococcioni]

Dear Prasenjit,

I do not know the answer to your question (it probably depends on the
details of the DOS of your system) but the situation does not look tragic
to me.
I guess you can always expect a departure from linearity when the
perturbation grows bigger. typically I use values within -0.1 and 0.1.
Why the interacting response is more well behaved than the other? I am not
sure. maybe it's because the screenening lowers the effective magnitude of
the perturbation and so it's like you have been using a smaller alpha.

Hope this helps,

Matteo

On Wed, May 27, 2015 at 9:13 AM, Prasenjit Ghosh 
wrote:

> Dear all,
>
> I am using linear response to determine U for Fe. In my system, there are
> two types of Fe atom, one in which the Fe is in an O octahedron and the
> second in which it is in an O terahedron.
> When I am plotting the occupation number of the Fe d as a function of
> perturbation alpha (-0.2 .le. alpha .le 0.2), for the non interacting
> electron system, I am not getting a linear plot for the whole range of
> alpha while for the interacting one it remains linear.
> For example when Fe is in the O octahedra, the response does not remain
> linear for alpha is greater than 0.05 or less than -0.05. However, for the
> interacting case, it remains linear for the whole regime (please refer to
> the attached plot for Fe in O octahedra).
> Further for this case for alpha=0, the occupation for the interacting and
> non interacting ones are not exactly same. While for the non-interacting
> one the occupation is 6.60012, it is 6.60162 for the interacting one.
>
> Similarly for the tethedra, for alpha=-0.2, the non-interacting response
> does not remain linear while for the interacting one it remains linear.
>
> I was wondering whether one has faced similar situations and if so can
> provide me some hints as to what might be the probable reason for the same?
>
> Below is the input file I am using for the calculation:
>
> for alpha in -0.20 -0.15 -0.10 -0.05 0.00 0.05 0.10 0.15 0.20
>
> do
>
> mkdir /scratch/pghosh/octfe/alpha$alpha
>
> cd /scratch/pghosh/octfe/alpha$alpha
>
> ethr=`grep ethr /home/pghosh/Ca2Fe2O5/octfe/scf.out | tail -1 | awk
> '{print $3}'`
>
> rm -rf Ca2Fe2O5-noU-vcrel-AFM.*
>
> cp -r ../Ca2Fe2O5-noU-vcrel-AFM.* .
>
> cat > scf-octFe.$alpha.in << EOF
>  &control
> calculation = 'scf',
> prefix = 'Ca2Fe2O5-noU-vcrel-AFM',
> outdir = '/scratch/pghosh/octfe/alpha$alpha'
> pseudo_dir = '/home/pghosh/pseudo'
>  /
>  &system
> ibrav =  0,
> celldm(1)=10.25176385
> nat = 36,
> ntyp = 5,
> ecutwfc = 45
> ecutrho = 320
> nspin=2
> starting_magnetization(2)=-1.0
> starting_magnetization(3)=1.0
> starting_magnetization(4)=-1.0
> occupations='smearing'
> degauss=0.001
> smearing='gaussian'
> lda_plus_u = .true.,
> U_projection_type = 'atomic',
> Hubbard_U(2) = 1.d-10
> Hubbard_U(3) = 1.d-10
> Hubbard_U(4) = 1.d-10
> Hubbard_U(5) = 1.d-10
> Hubbard_alpha(4) = $alpha
>  /
>  &electrons
> mixing_beta = 0.3
>  conv_thr = 1.0d-8,
> startingwfc = 'file',
> startingpot = 'file',
> diago_thr_init = $ethr
>  /
>
> ATOMIC_SPECIES
>  Ca 87.62 Ca.pw91-nsp-van.UPF
>  Fe1 47.867 Fe.pw91-sp-van_ak.UPF
>  Fe2 47.867 Fe.pw91-sp-van_ak.UPF
>  Fe3 47.867 Fe.pw91-sp-van_ak.UPF
>  O 15.999 O.pw91-van_ak.UPF
> ATOMIC_POSITIONS (crystal)
> Ca   0.479439516   0.108738866   0.023376810
> Ca   0.979439516   0.391261134   0.476623190
> Ca   0.520560484   0.608738866   0.976623190
> Ca   0.020560484   0.891261134   0.523376810
> Ca   0.520560484   0.891261134   0.976623190
> Ca   0.020560484   0.608738866   0.523376810
> Ca   0.479439516   0.391261134   0.023376810
> Ca   0.979439516   0.108738866   0.476623190
> Fe3  0.0   0.0  -0.0
> Fe1  0.5   0.5   0.5
> Fe1  0.0   0.5  -0.0
> Fe1  0.5  -0.0   0.5
> Fe2  0.948517158   0.25000   0.935170308
> Fe2  0.448517158   0.25000   0.564829692
> Fe2  0.051482842   0.75000   0.064829692
> Fe2  0.551482842   0.75000   0.435170308
> O0.262959232   0.985181682   0.237331409
> O0.762959232   0.514818318   0.262668591
> O0.737040768   0.485181682   0.762668591
> O0.237040768   0.014818318   0.737331409
> O0.737040768   0.014818318   0.762668591
> O0.237040768   0.485181682   0.737331409
> O0.262959232   0.514818318   0.237331409
> O0.762959232   0.985181682   0.262668591
> O0.027189198   0.140319152   0.069344138
> O0.527189198   0.359680848   0.430655862
> O0.972810802   0.640319152   0.930655862
> O0.472810802   0.859680848   0.569344138
> O0.972810802   0.859680848   0.930655862
> O0.472810802   0.640319152   0.569344138
> O0.027189198   0.359680848   0.069344138
> O0.527

Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)

[Matteo Cococcioni]

Dear Wajood,

to be precise: the starting_ns_eigenvalue flag allows you to change the
eigenvalue keeping the eigenvector fixed at what it was after the first
iteration (i.e., when the first non trivial occupation matrix is obtained).
But I still do not understand what you want to do. What is the difference
between "filling of d levels" and "eigenvalues of the occupation matrix"?
What do you mean exactly for "d levels"? If you mean Kohn-Sham states yes,
you can change their occupations (there is a card to do that, after you
choose occupations = 'from_input" if I'm not wrong) but they are not going
to be purely d states (i.e. they are not going to correspond exactly to
Bloch sums of atomic d states). Maybe some will but it all depends on the
electronic structure of the system.

Matteo

On Wed, Mar 25, 2015 at 2:53 PM, Wajood A Diery  wrote:

>  Dear Matteo,
> I dont think this is what am doing. As far as I understand, 
> starting_ns_eigenvalue(m,ispin,I)
> overwrites the mth eigenvalue not the occupation matrix it self. My
> question was if i can define the occupation matrix that corresponds to
> different filling of the d levels.
> Best
> Wajood
>
>  --
> *From:* pw_forum-boun...@pwscf.org [pw_forum-boun...@pwscf.org] on behalf
> of Matteo Cococcioni [mat...@umn.edu]
> *Sent:* 25 March 2015 09:24
> *To:* PWSCF Forum
> *Subject:* Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)
>
>Dear Wajood,
>
>  isn't this what you are already doing?
>
>  Matteo
>
> On Wed, Mar 25, 2015 at 11:33 AM, Wajood A Diery  wrote:
>
>>  Thank you so much.  One more question: is there a way in quantum
>> espresso to control the occupation matrix where the user can define the
>> occupation of the orbital in the occupation matrix?
>> Best
>> Wajood
>>  --
>> *From:* pw_forum-boun...@pwscf.org [pw_forum-boun...@pwscf.org] on
>> behalf of Matteo Cococcioni [mat...@umn.edu]
>> *Sent:* 24 March 2015 13:56
>> *To:* PWSCF Forum
>> *Subject:* Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)
>>
>>Dear Wajood,
>>
>>  it is not a problem. the eigenvalues are printed in growing order. the
>> important thing is that you get the xz state corresponding to the 0
>> eigenvalue. and it seems to be the case (although it is not a pure xz and
>> has a component on z^2)
>>
>>  regards,
>>
>>  Matteo
>>
>> On Tue, Mar 24, 2015 at 6:30 PM, Wajood A Diery  wrote:
>>
>>>  Dear Pwscf users,
>>> I have few questions about starting_ns_eigenvalue(m,ispin,I) and the
>>> occupation matrix for DFT+U. Am trying to fix the occupation of the d
>>> orbitals in Mn in BiMnO3. I've used starting_ns_eigenvalue(m,ispin,I) to
>>> specify the following occupation: 4 electrons in dz2, dyz, dx2-y2 and dxy
>>> and zero occupation for dxz. I was expecting to get eigenvalues such as
>>> 1.000  0.000  1.000  1.000  1.000, which give the occupation of the
>>> d-orbital,  but I got  0.000  1.000  1.000  1.000  1.000?  i've tried
>>> different occupations of the d-orbital and I always  get the same
>>> occupation or eigenvalues : 0.000  1.000  1.000  1.000  1.000? I am not
>>> sure if I miss understand the statring_ns_eigenvalue tag or there is
>>> something else that am missing? any help or suggestion will  be
>>> appreciated.
>>> Wajood
>>> Mechanical Engineering Department
>>> MIT
>>> This is the part of the input file related to my Question
>>> &system
>>> ibrav = 0,
>>>  celldm(1)= 18.013436
>>> nat = 40,
>>> ntyp = 3,
>>> ecutwfc = 60,
>>> nspin = 2,
>>> starting_magnetization(2)=1,
>>>occupations='smearing', smearing='gauss',
>>> degauss=0.01
>>>lda_plus_u=.true.
>>>lda_plus_u_kind=1
>>>  Hubbard_U(2)=8
>>> Hubbard_J(1,2)=1.06
>>> starting_ns_eigenvalue(1,1,2)=1.0,
>>> starting_ns_eigenvalue(2,1,2)=0.0,
>>> starting_ns_eigenvalue(3,1,2)=1.0,
>>> starting_ns_eigenvalue(4,1,2)=1.0,
>>> starting_ns_eigenvalue(5,1,2)=1.0,
>>>
>>>
>>> The output file is:
>>> LDA+U parameters:
>>> U(  2) =   8.   J(  2) =   1.0600   B(  2) =   0.1217
>>> atom9   Tr[ns(na)] (up, down, total) =   4.0  0.19494  4.19494
>>>spin  1
>>> eigenvalues:
>>>   0.000  1.000  1.000  1.000  1.000
>>> eigenvectors:
>>>   0.110  0.701  0.

Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)

[Matteo Cococcioni]

Dear Wajood,

isn't this what you are already doing?

Matteo

On Wed, Mar 25, 2015 at 11:33 AM, Wajood A Diery  wrote:

>  Thank you so much.  One more question: is there a way in quantum
> espresso to control the occupation matrix where the user can define the
> occupation of the orbital in the occupation matrix?
> Best
> Wajood
>  --
> *From:* pw_forum-boun...@pwscf.org [pw_forum-boun...@pwscf.org] on behalf
> of Matteo Cococcioni [mat...@umn.edu]
> *Sent:* 24 March 2015 13:56
> *To:* PWSCF Forum
> *Subject:* Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)
>
>Dear Wajood,
>
>  it is not a problem. the eigenvalues are printed in growing order. the
> important thing is that you get the xz state corresponding to the 0
> eigenvalue. and it seems to be the case (although it is not a pure xz and
> has a component on z^2)
>
>  regards,
>
>  Matteo
>
> On Tue, Mar 24, 2015 at 6:30 PM, Wajood A Diery  wrote:
>
>>  Dear Pwscf users,
>> I have few questions about starting_ns_eigenvalue(m,ispin,I) and the
>> occupation matrix for DFT+U. Am trying to fix the occupation of the d
>> orbitals in Mn in BiMnO3. I've used starting_ns_eigenvalue(m,ispin,I) to
>> specify the following occupation: 4 electrons in dz2, dyz, dx2-y2 and dxy
>> and zero occupation for dxz. I was expecting to get eigenvalues such as
>> 1.000  0.000  1.000  1.000  1.000, which give the occupation of the
>> d-orbital,  but I got  0.000  1.000  1.000  1.000  1.000?  i've tried
>> different occupations of the d-orbital and I always  get the same
>> occupation or eigenvalues : 0.000  1.000  1.000  1.000  1.000? I am not
>> sure if I miss understand the statring_ns_eigenvalue tag or there is
>> something else that am missing? any help or suggestion will  be
>> appreciated.
>> Wajood
>> Mechanical Engineering Department
>> MIT
>> This is the part of the input file related to my Question
>> &system
>> ibrav = 0,
>>  celldm(1)= 18.013436
>> nat = 40,
>> ntyp = 3,
>> ecutwfc = 60,
>> nspin = 2,
>> starting_magnetization(2)=1,
>>occupations='smearing', smearing='gauss',
>> degauss=0.01
>>lda_plus_u=.true.
>>lda_plus_u_kind=1
>>  Hubbard_U(2)=8
>> Hubbard_J(1,2)=1.06
>> starting_ns_eigenvalue(1,1,2)=1.0,
>> starting_ns_eigenvalue(2,1,2)=0.0,
>> starting_ns_eigenvalue(3,1,2)=1.0,
>> starting_ns_eigenvalue(4,1,2)=1.0,
>> starting_ns_eigenvalue(5,1,2)=1.0,
>>
>>
>> The output file is:
>> LDA+U parameters:
>> U(  2) =   8.   J(  2) =   1.0600   B(  2) =   0.1217
>> atom9   Tr[ns(na)] (up, down, total) =   4.0  0.19494  4.19494
>>spin  1
>> eigenvalues:
>>   0.000  1.000  1.000  1.000  1.000
>> eigenvectors:
>>   0.110  0.701  0.037  0.000  0.153
>>   0.795  0.016  0.023  0.000  0.166
>>   0.000  0.004  0.885  0.000  0.111
>>   0.096  0.279  0.055  0.000  0.570
>>   0.000  0.000  0.000  1.000  0.000
>> occupations:
>>   0.890 -0.295  0.000 -0.102  0.000
>>  -0.295  0.205  0.000 -0.276  0.000
>>   0.000  0.000  1.000  0.000  0.000
>>  -0.102 -0.276  0.000  0.904  0.000
>>   0.000  0.000  0.000  0.000  1.000
>>spin  2
>> eigenvalues:
>>   0.020  0.020  0.021  0.065  0.070
>> eigenvectors:
>>   0.000  0.512  0.416  0.071  0.000
>>   0.000  0.004  0.193  0.803  0.000
>>   0.542  0.000  0.000  0.000  0.458
>>   0.000  0.484  0.390  0.126  0.000
>>   0.458  0.000  0.000  0.000  0.542
>> occupations:
>>   0.023  0.010  0.000  0.005  0.000
>>   0.010  0.056  0.000  0.014  0.000
>>   0.000  0.000  0.043  0.000 -0.025
>>   0.005  0.014  0.000  0.026  0.000
>>   0.000  0.000 -0.025  0.000  0.047
>> atomic mag. moment = 3.805060
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum@pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] DFT+U and starting_ns_eigenvalue(m,ispin,I)

[Matteo Cococcioni]

Dear Wajood,

it is not a problem. the eigenvalues are printed in growing order. the
important thing is that you get the xz state corresponding to the 0
eigenvalue. and it seems to be the case (although it is not a pure xz and
has a component on z^2)

regards,

Matteo

On Tue, Mar 24, 2015 at 6:30 PM, Wajood A Diery  wrote:

>  Dear Pwscf users,
> I have few questions about starting_ns_eigenvalue(m,ispin,I) and the
> occupation matrix for DFT+U. Am trying to fix the occupation of the d
> orbitals in Mn in BiMnO3. I've used starting_ns_eigenvalue(m,ispin,I) to
> specify the following occupation: 4 electrons in dz2, dyz, dx2-y2 and dxy
> and zero occupation for dxz. I was expecting to get eigenvalues such as
> 1.000  0.000  1.000  1.000  1.000, which give the occupation of the
> d-orbital,  but I got  0.000  1.000  1.000  1.000  1.000?  i've tried
> different occupations of the d-orbital and I always  get the same
> occupation or eigenvalues : 0.000  1.000  1.000  1.000  1.000? I am not
> sure if I miss understand the statring_ns_eigenvalue tag or there is
> something else that am missing? any help or suggestion will  be
> appreciated.
> Wajood
> Mechanical Engineering Department
> MIT
> This is the part of the input file related to my Question
> &system
> ibrav = 0,
>  celldm(1)= 18.013436
> nat = 40,
> ntyp = 3,
> ecutwfc = 60,
> nspin = 2,
> starting_magnetization(2)=1,
>occupations='smearing', smearing='gauss',
> degauss=0.01
>lda_plus_u=.true.
>lda_plus_u_kind=1
>  Hubbard_U(2)=8
> Hubbard_J(1,2)=1.06
> starting_ns_eigenvalue(1,1,2)=1.0,
> starting_ns_eigenvalue(2,1,2)=0.0,
> starting_ns_eigenvalue(3,1,2)=1.0,
> starting_ns_eigenvalue(4,1,2)=1.0,
> starting_ns_eigenvalue(5,1,2)=1.0,
>
>
> The output file is:
> LDA+U parameters:
> U(  2) =   8.   J(  2) =   1.0600   B(  2) =   0.1217
> atom9   Tr[ns(na)] (up, down, total) =   4.0  0.19494  4.19494
>spin  1
> eigenvalues:
>   0.000  1.000  1.000  1.000  1.000
> eigenvectors:
>   0.110  0.701  0.037  0.000  0.153
>   0.795  0.016  0.023  0.000  0.166
>   0.000  0.004  0.885  0.000  0.111
>   0.096  0.279  0.055  0.000  0.570
>   0.000  0.000  0.000  1.000  0.000
> occupations:
>   0.890 -0.295  0.000 -0.102  0.000
>  -0.295  0.205  0.000 -0.276  0.000
>   0.000  0.000  1.000  0.000  0.000
>  -0.102 -0.276  0.000  0.904  0.000
>   0.000  0.000  0.000  0.000  1.000
>spin  2
> eigenvalues:
>   0.020  0.020  0.021  0.065  0.070
> eigenvectors:
>   0.000  0.512  0.416  0.071  0.000
>   0.000  0.004  0.193  0.803  0.000
>   0.542  0.000  0.000  0.000  0.458
>   0.000  0.484  0.390  0.126  0.000
>   0.458  0.000  0.000  0.000  0.542
> occupations:
>   0.023  0.010  0.000  0.005  0.000
>   0.010  0.056  0.000  0.014  0.000
>   0.000  0.000  0.043  0.000 -0.025
>   0.005  0.014  0.000  0.026  0.000
>   0.000  0.000 -0.025  0.000  0.047
> atomic mag. moment = 3.805060
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Clarification on Calculating U based on linear response

[Matteo Cococcioni]

Dear Joshua

On Mon, Mar 2, 2015 at 4:27 PM, Joshua Davis 
wrote:

> Dear QE Users
>
> I want to know how to calculate U based on linear response
> , but I
> am having trouble understanding what occupation values to use from a
> calculation for a response matrix.
>
> I have fallowed the tutorials
>
>
> http://media.quantum-espresso.org/santa_barbara_2009_07/slides-exercices/Handson_ldau.pdf
>
> and
>
> http://hjklol.mit.edu/content/calculating-hubbard-u
>
>
>
you have to use the trace of the occupation matrix.



> Do I use the Trace of the d-electron occupation matrix (like in the first
> link) or am I to use sum of all the elements of the matrix (like in the
> second link)?
>
> Secondly when calculating U, if the atoms that require a U are not very
> close to each other, can you get away with not calculating the off-diagonal
> response matrix elements and just invert the diagonal response matrix
> elements directly?
>


I guess it depend on the system you are considering. just try in one case
and see how results compare.

Matteo



>
> I am using QE 5.1.
> Thanks for any help
>
> 
> Joshua D. Davis
>
> Graduate Assistant
> Department of Chemistry
> Michigan State University
>
> East Lansing, MI 48824
>
> -
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Inconsistent U(Fe,oct) and U(Fe,tet) in Fe3O4

[Matteo Cococcioni]

dear Xu

looks like that the calculation in one of the cells you are using (or maybe
both) is not converged with the size of the cell.
The linear response calculation of U is only sensitive to the distance and
the number of neighbors. As long as the supercell you are using guarantees
that each Fe (of each type) has the correct number of neighbors at the
correct distance, the result should be the same.

Matteo

On Tue, Feb 3, 2015 at 2:55 AM,  wrote:

> Hi,
>
> I'm calculating the Hubbard U for Fe (octahedral) and Fe (tetrahedral) in
> bulk Fe3O4. The ultrasoft pseudopotential (USPP) I'm using now was
> downloaded from QE website called "Fe.pbe-nd-rrkjus.UPF". I'm using
> QE-5.0.2-pgi-13.4
>
> But I got inconsistent U(Fe,oct) and U(Fe,tet) values when I use different
> type of cell to do the linear perturbation. When I use cubic cell (56 atoms
> in total, 16 Fe_oct, 8 Fe_tet and 32 O), I got U(Fe,oct) < U(Fe,tet). When
> I use hexagonal cell (42 atoms in total, 12 Fe_oct, 6 Fe_tet and 24 O), or
> rhombohedral primitive cell (14 atoms in total, 4 Fe_oct, 2 Fe_tet and 8
> O), I got U(Fe,oct) > U(Fe,tet).
>
> I changed the CELL_PARAMETERS to make the Fe_oct and Fe_tet in cubic cell
> have the same Fe-O bond directions as those in hexagonal or rhombohedral
> cell. But still, it gave U(Fe,oct) < U(Fe,tet).
>
> I don't know if the problem is from the USPP or from the linear
> perturbation theory itself implemented in QE. People keep treating these
> two types of Fe the same in magnetite Fe3O4 studies. I read papers from
> Emily Carter's group using different U(Fe,oct) and U(Fe,tet). But their U
> values were not derived by calculation or by Fe3O4 itself, but from
> empirical combination obtained by FeO and Fe2O3. I got stuck with those
> inconsistent U values of Fe3O4 from QE and have no idea about how to deal
> with it.
>
> Thank you,
> Xu Huang
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] halp

[Matteo Cococcioni]

I do not know anything about this compound. I assume you want to
distinguish Cr atoms into two groups to assign them opposite magnetization
(for the AFM case), is this right?
If this is the case you do not have any problem for the FM as all the Cr
can be treated as of the same kind and assigned the same magnetization. In
any case you just need a starting_magnetization (between 0 and 1) for each
kind of Cr different from 0, the value is not very important (it is
re-computed anyway during the calculation). If you read the manual you find
plenty of explanation about this.
In the AFM case you just need to assign half of them spin up and the other
half spin down (positive or negative starting_magnetization, respectively),
after specifying them as of two different kinds (albeit corresponding to
the same pseudopotential, as in the NiO case). Of course, the energy will
probably change depending on which ones you pick as up and downs, but it is
your job to find the ground state magnetic configuration of the system.

hope this helps clarifying your questions.

Please share your name and affiliation.

Matteo



On Tue, Jan 20, 2015 at 7:50 AM, N Bolandhemat 
wrote:

> Dear all
> I am calculating the FM and AFM properties of CdCr2O4 with the 4 atoms of
> Cr in fourteen-atom CdCr2O4 unit cell.In order to run the scf calculation
> for FM in a cubic structure I have a few problems if anyone can help me: 1.
> how can I find the actual number of starting_magnetization? 2. how can I
> identify the different Cr (1 and 2) in the ATOMIC_POSITION as i have 4 Cr?
> (below is the scf code of my compound and fallowing that the NiO magnetic
> example that I am fallowing)
>
> scf code of CdCr204(FM)
> &control
> calculation='scf'
> /
> &system
>  ibrav = 2,
>  celldm(1)= 16.3782,
>  .
>  .
>  nspin=2,
>  starting_magnetization(1)= ?
>  starting_magnetization(2)= ?
> /
> &ELECTRONS
>
> /
> CELL_PARAMETERS
>
> ATOMIC_SPECIES
> Cr1  51.9961  Cr.pbe-sp-van.UPF
> Cr2  51.9961  Cr.pbe-sp-van.UPF
> Cd   112.411  Cd.pbe-n-van.UPF
> O15.9994   O.pbe-van_ak.UPF
> ATOMIC_POSITIONS (crystal)
> Cr ?   0.5   0.0   0.5
> Cr ?   0.0   0.5   0.5
> Cr ?   0.5   0.5   0.0
> Cr ?   0.5   0.5   0.5
> Cd   0.12500   0.12500   0.12500
> Cd   0.87500   0.87500   0.87500
> O0.731036464   0.731036464   0.731036464
> O0.268963536   0.268963536   0.693109391
> O0.268963536   0.693109391   0.268963536
> O0.693109391   0.268963536   0.268963536
> O0.731036464   0.306890609   0.731036464
> O0.306890609   0.731036464   0.731036464
> O0.268963536   0.268963536   0.268963536
> O0.731036464   0.731036464   0.306890609
>
> scf code of NiO(FM)
>
> &control
> pseudo_dir = '../../pseudo',
> outdir='../../tmp'
> prefix='nio',
> /
> &system
> nspin=2,
> starting_magnetization(2)= 0.5,
> starting_magnetization(3)=0.5,
> /
> &electrons
> /
> CELL_PARAMETERS
> ATOMIC_SPECIES
> O1.  O.pbe-rrkjus.UPF
> Ni1  1.  Ni.pbe-nd-rrkjus.UPF
> Ni2  1.  Ni.pbe-nd-rrkjus.UPF
> ATOMIC_POSITIONS crystal
> O  0.25 0.25 0.25
> O  0.75 0.75 0.75
> Ni1 0.0  0.0  0.0
> Ni2 0.5  0.5  0.5
> K_POINTS automatic
> 4 4 4 0 0 0
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Question regarding Hubbard U

[Matteo Cococcioni]

Dear Youssef,

you should perturb all the atoms (one each kind) you want the U for. in the
position file for r.x list of the atoms of Hubbard kind (the ones you have
perturbed and those of the same kind).

Hope this helps,

Matteo

On Wed, Jan 14, 2015 at 2:48 PM, Youssef Aharbil  wrote:

> Dear Quantum espresso community and Dear Dr Matteo,
>
> I have a question about how to deal with compound with mixed elemnts > 3
> (eg : with 3d open or clos shell , 2p sell ...), how can we compute U?
>
> Should I perturb all the elements even for those without  d or f  shell
> likewise the case of oxygen (eg: Al in presence of Fe in my case) , if
> not , should I take them in consideration on r.x input (position input file)
>
> Thank you in advance.
>
>
>
>
> Youssef Aharbil
> PhD
> Laboratory of Physics and Chemistry of Material
> Morocco
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Error when running r.x for DFT+U

[Matteo Cococcioni]

Dear Ariadna,

I do not understand what your question is. Your file looks good (does it
still give you error?)
In any case the first three lines are supposed to be the unit cell vector.
They are followed by (crystal) atomic positions.
The scale is not important. The unit cell vectors are used by the code to
compute interatomic distances and recognize shells of equivalent neighbors.

Regards,

Matteo

On Fri, Jan 16, 2015 at 2:43 PM, Ariadna Blanca Romero <
a.blanca-rom...@imperial.ac.uk> wrote:

> Thank you Matteo,
>
> It seems that the problem was the number of characters in the name of my
> files, they are too long—they should be less than 20 characters. However, I
> still have the question regarding the lattice vectors in pos.in file.
>
> My Fe_conventional.pos.in:
>
> 5.3526  0.0 0.0
> 0.0 5.3526  0.0
> 0.0 0.05.3526
> 0.0  0.0   0.0
> 0.5  0.5   0.5
>
> In this case my file differs from the one of Matteo (which I will append
> bellow) because I understood that the first three lines should be the
> lattice vectors, and in this case it is a cubic structure. I used my
> optimized lattice constant for Bulk Fe that is 5.3526 Bohr. The next two
> lines are the position of the atoms.
>
> Here is the pos.in of Matteo’s example:
>
> 10.d0 0.d0 0.d0
> 0.d0 10.d0 0.d0
> 0.d0 0.d0 10.d0
> 0.d0 0.d0 0.d0
> 0.5d0 0.5d0 0.5d0
>
> Regards,
>
> Ariadna
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Error when running r.x for DFT+U

[Matteo Cococcioni]

Dear Ariadna,

try to open resp_mat.f90 and check what it expects to read from the file
connected to unit 11. It looks like it is not finding all the information
it expects.

Regards,

Matteo

On Thu, Jan 15, 2015 at 10:00 AM, Ariadna Blanca Romero <
a.blanca-rom...@imperial.ac.uk> wrote:

> Dear users and Matteo,
>
> I complied successfully the resp_mat.f90 that comes along with Matteo’s
> tutorial of the school 2009. I wanted to test it using the simplest example
> of bulk Fe (the conventional cell with two atoms) as in the example of the
> tutorial. When I try to run r.x < res_mat.in I got the next error:
>
> forrtl: severe (24): end-of-file during read, unit 11,
> file 
> /export91/work/ablancar/QE/Work/PBE+U_work/ULR/Fe_conventional/PERTURBED/Fe_conventional.pos.
> Image  PCRoutineLine
>   Source
> r.x00A2F2CE  Unknown   Unknown  Unknown
> r.x00A2DD66  Unknown   Unknown  Unknown
> r.x009EBB42  Unknown   Unknown  Unknown
> r.x009ABBEB  Unknown   Unknown  Unknown
> r.x009AB152  Unknown   Unknown  Unknown
> r.x009BCE40  Unknown   Unknown  Unknown
> r.x0040ADD2  Unknown   Unknown  Unknown
> r.x004095DC  Unknown   Unknown  Unknown
> libc.so.6  00368121ECDD  Unknown   Unknown  Unknown
> r.x004094D9  Unknown
>   Unknown  Unknown
>
> For the perturbations I did  (-0.1,-0.05, 0, 0.05,0.1).
>
> This is my res_mat.in file:
>
> &input_mat
>  ntyp = 1
>  na(1) = 2
>  nalfa = 5
>  filepos = 'Fe_conventional.pos.in'
>  back = 'neutral'
>  filednda = 'dnda_Fe_conventional.in'
>  n1 = 5
>  n2 = 5
>  n3 = 5
> &end
>
> My Fe_conventional.pos.in:
>
> 5.3526  0.0 0.0
> 0.0 5.3526  0.0
> 0.0 0.05.3526
> 0.0  0.0   0.0
> 0.5  0.5   0.5
>
> In this case my file differs from the one of Matteo (which I will append
> bellow) because I understood that the first three lines should be the
> lattice vectors, and in this case it is a cubic structure. I used my
> optimized lattice constant for Bulk Fe that is 5.3526 Bohr. The next two
> lines are the position of the atoms.
>
> Here is the pos.in of Matteo’s example:
>
> 10.d0 0.d0 0.d0
> 0.d0 10.d0 0.d0
> 0.d0 0.d0 10.d0
> 0.d0 0.d0 0.d0
> 0.5d0 0.5d0 0.5d0
>
> Here the lattice vectors are different, why is 10 Bohr instead 5.42 Bohr
> as the lattice constant that was used in the example? The error I get could
> be related to this file? I noticed that after running  r.x an empty file
> called “Fe_conventional.pos.” is generated when I get the error mentioned
> above.
>
> Mydnda_Fe_conventional.in is:
> dn_1_da_1_Fe_conventional.dat  dn0_1_da_1_Fe_conventional.dat
> dn_2_da_1_Fe_conventional.dat  dn0_2_da_1_Fe_conventional.dat
>
> My dn files are:
> dn_1_da_1_Fe_conventional.dat:
> -0.10 7.24564
> -0.05 7.23595
> 0.00 7.22621
> 0.05 7.21643
> 0.10 7.20658
> dn_2_da_1_Fe_conventional.dat:
> -0.10 7.21616
> -0.05 7.22119
> 0.00 7.22622
> 0.05 7.23126
> 0.10 7.23633
> dn0_1_da_1_Fe_conventional.dat:
> -0.10 6.66416
> -0.05 6.64489
> 0.00 6.62575
> 0.05 6.60679
> 0.10 6.58807
> dn0_2_da_1_Fe_conventional.dat:
> -0.10 6.60641
> -0.05 6.61609
> 0.00 6.62575
> 0.05 6.63541
> 0.10 6.64510
>
> Hope you can give me some advise and thanks for the time.
>
> Kind regards,
>
> Ariadna
>
> ––
> Dr. Ariadna Blanca Romero
> Research Associate
> Imperial College London
>
>
>
>
>
>
>
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Re : how to calculate U parameter

[Matteo Cococcioni]

Dear Swati,

I do not know much about ZnSe and cannot answer your first question.
Usually the +U correction is applied to atoms with d or f electrons.
As for changing the routines it should self-evident once you open them. In
set_hubbard_l you choose the l quantum number  you want to apply the U to
for a specific atom (e.g., if you correct the d states of Fe you pick l = 2
for Fe). In tabd, instead, you choose the total number of electrons (spin
up + spin down) the code places on the selected orbitals
(e.g., for Fe it is usually 6).

Hope this helps.

Matteo

On Sat, Jan 10, 2015 at 7:24 AM, Swati Khatta 
wrote:

> Dear Matteo
>
> As extension to my previous question, I still have a queries that is it
> sufficient to apply U parameter on only Zn as it is 3d element . As Se is
> 4p element so it is also necerssarily required  to apply U parameter on it
> as I do further calucations on ZnSe system And if so so how to update
> rotines set _hubbaed_l.f90 and tabd.f90.
>
>  Regards
>  swati khatta
>   panjab University
>   chandigarh
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] how to calculate U parameter

[Matteo Cococcioni]

Dear Virginie,

this is not possible at the moment, but there are plans to add this
extension to the code. Hopefully it will be available in the near future.

Best regards,

Matteo



On Fri, Jan 9, 2015 at 10:17 AM, TRINITE Virginie <
virginie.trin...@thalesgroup.com> wrote:

>  Dear All
>
>
>
> I have a related question, coming from elements with semicore states :
>
> Is it possible to have more that one orbital by atoms corrected by the U?
>
> I was thinking that maybe for 3d and 4d elements, it will be meaningful to
> correct not only the d part but also the semicore states that are very
> localized.
>
>
>
> Best Regards
>
>
>
> Dr Virginie Trinite
>
> ---
>
> Modeling Infra-Red Lasers and Detectors
>
> III-V Lab THALES Research&  Technology, France
>
>
>
> Campus Polytechnique
>
> 1, avenue Augustin Fresnel 91767 Palaiseau cedex France
>
>
>
> *De :* pw_forum-boun...@pwscf.org [mailto:pw_forum-boun...@pwscf.org] *De
> la part de* Matteo Cococcioni
> *Envoyé :* vendredi 9 janvier 2015 00:06
> *À :* PWSCF Forum
> *Objet :* Re: [Pw_forum] how to calculate U parameter
>
>
>
>
>
> Dear Swati,
>
> one possibility is to compute U from linear response as we proposed some
> year ago in PRB 71 35105 (2005). You can also find a tutorial on this on
> the webpage:
> http://media.quantum-espresso.org/santa_barbara_2009_07/.
>
> As for Se do you really need to use U on it? if so, you have to update the
> routines set_hubbard_l.f90 and tabd.f90 in order to tell the code what
> orbital shoudl be corrected by U and how many electrons it should put on
> them at the beginning of calculation. These routines are contained inside
> the flib and PW/src/ directories of the code which you then need to
> recompile.
>
> Best regards,
>
> Matteo
>
>
>
> On Thu, Jan 8, 2015 at 6:42 PM, Swati Khatta 
> wrote:
>
> Dear all,
>
> I would like to do calculations with  DFT+U of ZnSe material using Quantum
> esspresso. As per I know there is different U for each distinct type of
> hubbard atom.And typical value of U is rarely larger than 7-8 eV and in
> most case it lies between 0 satisfied for Zn  atom .Is there we do any type of convergence  to
> calculate U parameter.
>
> And in case we include U parameter for Se the error has ocurred '
> pseduopotential is not inserted yet'. So is it sufficient to not include U
> parameter for Se to do DFT+U calculations for ZnSe.
>
> Regards
>
> swati khatta
>
> panjab University
>
> chandigarh
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] how to calculate U parameter

[Matteo Cococcioni]

Dear Swati,

one possibility is to compute U from linear response as we proposed some
year ago in PRB 71 35105 (2005). You can also find a tutorial on this on
the webpage:
http://media.quantum-espresso.org/santa_barbara_2009_07/.

As for Se do you really need to use U on it? if so, you have to update the
routines set_hubbard_l.f90 and tabd.f90 in order to tell the code what
orbital shoudl be corrected by U and how many electrons it should put on
them at the beginning of calculation. These routines are contained inside
the flib and PW/src/ directories of the code which you then need to
recompile.

Best regards,

Matteo

On Thu, Jan 8, 2015 at 6:42 PM, Swati Khatta  wrote:

> Dear all,
>
> I would like to do calculations with  DFT+U of ZnSe material using Quantum
> esspresso. As per I know there is different U for each distinct type of
> hubbard atom.And typical value of U is rarely larger than 7-8 eV and in
> most case it lies between 0 satisfied for Zn  atom .Is there we do any type of convergence  to
> calculate U parameter.
> And in case we include U parameter for Se the error has ocurred '
> pseduopotential is not inserted yet'. So is it sufficient to not include U
> parameter for Se to do DFT+U calculations for ZnSe.
>
> Regards
> swati khatta
> panjab University
> chandigarh
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Does considering 2*2*2 supercell is required while calculating LR U

[Matteo Cococcioni]

On Tue, Nov 18, 2014 at 7:11 PM, SRKC Sharma Yamijala <
sharmajnc...@gmail.com> wrote:

> Dear PW members,
>
> I have gone through the tutorials of LDA+U available online (mainly of
> Matteo Cococcioni and also his PRB 2005 paper). I am interested in
> calculating the U for the system SrVO3 and others. If I correctly follow
> the tutorial on NiO, to calculate U, I need calculate the scf with 2*2*2
> supercell (and with 4*4*4 etc. till U convergence) by keeping Ni at the
> origin once and by keeping O at the origin next. If I follow the above and
> consider the 2*2*2 supercell then the number of atoms in my system will be
> 40.
>
> But, I am guessing (I may be wrong) that supercell is considered because
> of the AFM nature of NiO ground state. So, can someone please clarify
> whether considering supercell is required for non-magnetic/Ferro-magnetic
> systems also or not?
>
>

Dear Sharma,

NiO needs a unit cell of 4 atoms becaus it is AFM. if it was FM it would be
possible to use a cell of 2 atoms only. In both cases you would need to
perform the linear response calculation of U in a supercell (of the
appropriate cell).

Hope this helps

Matteo




> Thanking you for your support,
> Sincerely,
> Sharma.
> 
> *Chaitanya Sharma,*
> *Prof. Pati'*s group,
> Chemistry and Physics Materials unit,
> JNCASR, BANGLORE,
> Lab:: (080-2208) 2581, 2809
> https://sites.google.com/site/sharmasrkcyamijala/
> *
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] how to fix the occupations in DFT+U

[Matteo Cococcioni]

Dear Simone

I try to answer your questions below.

On Fri, Nov 7, 2014 at 3:32 PM, simone marocchi 
wrote:

> Dear all, I am simulating compounds with rare earths within a collinear
> calculation. I tried to suggest some occupations of the f orbitals for the
> Tb atom, using the starting_ns_eigenvalue(m,ispin,I).
>


why do you need to do that? if you want to force different values of
occupation on states that are equivalent by symmetry you will not be
successful. If this is the case you have to do something that makes the
system loose that symmetry operation connecting the two states.



> Unfortunately also with a small value of electronic mixing and big values
> of U, the imposed occupations was lost during the iterative cycle.
>


this can happen. a dirty trick I learned recently is to suggest a
starting_ns_eigenvalue(m,
ispin,I) bigger than one in input (1.2 or 1.3 maybe). This does not make
any physical sense of course. However the Hubbard potential becomes more
attractive for the specific eigenvector of the occupation matrix you want
to fill completely and the code takes more time to "come back" to a
physical value. If that is a state it likes (at least a local minimum of
the energy) it might fall into it. Of course you have to check at the end
that the occupation has gone back to a value <= 1.



> So I used also mixing_fixed_ns > electron_maxstep. Also in this case after
> I obtain the total energy convergence the density matrix of the last
> iteration is different to the one imposed in the input_file.
>


this is (possibly) strange. How different is it? How well are you
converging?
The fact that it is different is not surprising: the routine that prints
the ns, always prints the ones that are computed from the KS states just
obtained from the new diagonalization. These can be different from the ones
e.g. used in contructing the Hubbard potential.
However if your calculation is well converged this difference should not be
big: both KS wfcs and their occupations should be converged reasonably well.
If this does not happen and you still see a significant difference maybe it
means that the values you are trying to impose is not consistent with what
the system wants to do (e.g., you have less symmetry than the code finds
for your crystal)




> Can someone of you kindly explain me how the mixing_fixed_ns works ? Do it
> uses a sort of Lagrange multipliers to force the occupations or is more
> like a penalty function ? Finally, is it possible to work around the
> problem, converging to a determined occupation ?
>


no with the current version of the code. you could implement some (e.g.,
quadratic) constraint and try. I think I once tried (long time ago) and
seem to remember problems in convergence.

Best,

Matteo




>
> Thanks in advance for every suggestion,
>
> Simone Marocchi
>
> S3 Center, Istituto Nanoscienze, CNR
> via Campi 213/A, 41125, Modena, Italy
> Tel: +39 *0592055585*;  Skype: jacobi84
> URL: http://www.nano.cnr.it
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

Re: [Pw_forum] Hubbard force discrepancies

[Matteo Cococcioni]

Dear Dmitry,

what you describe is probably true for all the components of the forces,
not just the Hubbard one. The reason is that the Hellmann-Feynman theorem,
used to compute the forces printed in the output, only applies to the total
energy, not to its separate components. In fact, the electronic wave
functions used in the calculation of the matrix elements are eigenstates of
the whole Hamiltonian, not of its pieces.
Of course, the code still compute the forces "piece by piece". So each of
those term is "wrong" (in the sense it does not equal the derivative of the
corresponding term of the energy) but when you sum them up together, these
errors cancel each other and you get the right force.


Regards,

Matteo




On Thu, Oct 23, 2014 at 10:24 AM, Dmitry Novoselov 
wrote:

> Dear all,
>
> I have performed the set of LSDA+U calculations to determine the Hubbard
> forces acting on Ni atom in a well-known NiO.
> For this purpose I was displacing one Ni atom in the x-direction up to 0.1
> angstroms with 0.025 angstroms step.
>
> How we know a force may be evaluate like:
> $F_{\alpha i} = -\frac{\partial E}{\partial \tau_{\alpha i}}$.
> That allows us to calculate a force by taking a numerical derivative of
> the energy with respect to the displacement $\tau_{\alpha i}$ by least
> square approximation for example.
>
> If I make it for the total energy (see total_energy.eps) I get a good
> agreement between analytical (x-component for the displaced Ni atom) and
> numerical value of the total force (see total_force.eps).
> But if I repeat it for the Hubbard energy (see hubbard_energy.eps) I get
> some discrepancy expressed in the mismatch between analytical (x-component
> for the displaced Ni atom) and numerical value of the Hubbard force (see
> hubbard_force.eps) with -0.5 factor (see expected_hubbard_force.eps).
>
> What can be the reason for this discrepancy?
>
> Thank you!
>
> P.S.
> The values of the energy and forces (x-component for the displaced Ni
> atom) obtained during the LSDA+U calculation respect to the displacement
> of one Ni atom in the x-direction are contained in the attached file result.
> dat.
>
> --
>
> *Best regards,*
>
>
> *Dr. Dmitry NovoselovInstitute for Metal Physics,*
> *Yekaterinburg, Russia*
>
>
> ___
> Pw_forum mailing list
> Pw_forum@pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
___
Pw_forum mailing list
Pw_forum@pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

[Pw_forum] LDA+U problem

[Matteo Cococcioni]

Hi

you also have written

lda_plus_u=.TURE.

instead of

lda_plus_u=.TRUE.

in your input file.

Matteo

On Mon, Oct 6, 2014 at 2:52 PM, Matteo Cococcioni  wrote:

>
> Then I would advice to look inside offset_atom_wfc (as the error message
> suggests) and to try to track what went wrong.
>
> On Mon, Oct 6, 2014 at 2:37 PM, Jiajie Zhu 
> wrote:
>
>>  Thank you.
>>
>> I have checked set_hubbard_l.f90 and tabd.f90 files and found all
>> rare-earth atoms are included.
>>
>>
>>
>> Jiajie
>>  --
>> *From:* pw_forum-bounces at pwscf.org [pw_forum-bounces at pwscf.org] on
>> behalf of Matteo Cococcioni [matteo at umn.edu]
>> *Sent:* Monday, October 06, 2014 3:06 PM
>> *To:* PWSCF Forum
>> *Subject:* Re: [Pw_forum] LDA+U problem
>>
>>Hi,
>>
>>  probably Eu is not in the list of known atoms for the +U functional. Try
>> to check inside set_hubbard_l and tabd routines.
>>
>>  Best,
>>
>> Matteo
>>
>> On Mon, Oct 6, 2014 at 1:53 PM, Jiajie Zhu 
>> wrote:
>>
>>>  Hello,
>>>
>>> I meet problems with error message "Error in routine offset_atom_wfc
>>> (48): wrong offset", when I try to do a LDA+U calculation. My system
>>> consists of W Se and Eu atoms and I apply U on Eu atom with following tags
>>> in &SYSTEM:
>>>
>>> lda_plus_u=.TURE.
>>> lda_plus_u_kind=0
>>> Hubbard_U(3) = 6.0  (Eu is the 3rd species)
>>>
>>> Anyone knows the solution?
>>>
>>> Thx
>>>
>>> Jiajie Zhu
>>>
>>>
>>> --
>>>
>>> This message and its contents including attachments are intended solely
>>> for the original recipient. If you are not the intended recipient or have
>>> received this message in error, please notify me immediately and delete
>>> this message from your computer system. Any unauthorized use or
>>> distribution is prohibited. Please consider the environment before printing
>>> this email.
>>>
>>> ___
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>
>>
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20141006/b9bffa38/attachment.html
 

[Pw_forum] LDA+U problem

[Matteo Cococcioni]

Then I would advice to look inside offset_atom_wfc (as the error message
suggests) and to try to track what went wrong.

On Mon, Oct 6, 2014 at 2:37 PM, Jiajie Zhu  wrote:

>  Thank you.
>
> I have checked set_hubbard_l.f90 and tabd.f90 files and found all
> rare-earth atoms are included.
>
>
>
> Jiajie
>  --
> *From:* pw_forum-bounces at pwscf.org [pw_forum-bounces at pwscf.org] on 
> behalf
> of Matteo Cococcioni [matteo at umn.edu]
> *Sent:* Monday, October 06, 2014 3:06 PM
> *To:* PWSCF Forum
> *Subject:* Re: [Pw_forum] LDA+U problem
>
>Hi,
>
>  probably Eu is not in the list of known atoms for the +U functional. Try
> to check inside set_hubbard_l and tabd routines.
>
>  Best,
>
> Matteo
>
> On Mon, Oct 6, 2014 at 1:53 PM, Jiajie Zhu 
> wrote:
>
>>  Hello,
>>
>> I meet problems with error message "Error in routine offset_atom_wfc
>> (48): wrong offset", when I try to do a LDA+U calculation. My system
>> consists of W Se and Eu atoms and I apply U on Eu atom with following tags
>> in &SYSTEM:
>>
>> lda_plus_u=.TURE.
>> lda_plus_u_kind=0
>> Hubbard_U(3) = 6.0  (Eu is the 3rd species)
>>
>> Anyone knows the solution?
>>
>> Thx
>>
>> Jiajie Zhu
>>
>>
>> --
>>
>> This message and its contents including attachments are intended solely
>> for the original recipient. If you are not the intended recipient or have
>> received this message in error, please notify me immediately and delete
>> this message from your computer system. Any unauthorized use or
>> distribution is prohibited. Please consider the environment before printing
>> this email.
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20141006/ef9d2d19/attachment.html
 

[Pw_forum] LDA+U problem

[Matteo Cococcioni]

Hi,

probably Eu is not in the list of known atoms for the +U functional. Try to
check inside set_hubbard_l and tabd routines.

Best,

Matteo

On Mon, Oct 6, 2014 at 1:53 PM, Jiajie Zhu  wrote:

>  Hello,
>
> I meet problems with error message "Error in routine offset_atom_wfc (48):
> wrong offset", when I try to do a LDA+U calculation. My system consists of
> W Se and Eu atoms and I apply U on Eu atom with following tags in &SYSTEM:
>
> lda_plus_u=.TURE.
> lda_plus_u_kind=0
> Hubbard_U(3) = 6.0  (Eu is the 3rd species)
>
> Anyone knows the solution?
>
> Thx
>
> Jiajie Zhu
>
>
> --
>
> This message and its contents including attachments are intended solely
> for the original recipient. If you are not the intended recipient or have
> received this message in error, please notify me immediately and delete
> this message from your computer system. Any unauthorized use or
> distribution is prohibited. Please consider the environment before printing
> this email.
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20141006/0e549709/attachment.html
 

[Pw_forum] Hubbard forces without Hubbard U

[Matteo Cococcioni]

Dear Dmitry,

it should be working. what version of the code are you using?

Matteo


On Wed, Aug 13, 2014 at 10:47 AM, Dmitry Novoselov 
wrote:

> Dear all,
>
> It seems that in the part of the code where the Hubbard forces is
> calculated (forces and force_hub subroutines), the Hubbard U correction
> does not taken into account. Is it ok?
>
> Thank you!
>
> --
>
>  *Best regards,*
>
>
> *Dr. Dmitry Novoselov Institute for Metal Physics,*
> *Yekaterinburg, Russia*
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140814/d47e2b57/attachment.html
 

[Pw_forum] Linear response method for J

[Matteo Cococcioni]

Dear Pietro,

keep in mind that the calculation of J with linear response is quite
tricky. In fact, as we mention in the paper, it only work if you start from
a non magnetic ground state. with a magnetic ground state, instead, gives
quite suspicious results. the reason is, I think, that the energy is not
variational with respect to the magnetization m.
For CuO we only measured J from GGA as the GGA ground state is non
magnetic.

hope this helps.

best,

Matteo


On Mon, Jun 30, 2014 at 4:51 PM, Pietro Bonfa' 
wrote:

> Dear PWscf users,
>
> I'm trying to estimate J with the linear response approach discussed in
> the article by Himmetoglu and colleagues (PRB 84, 115108 (2011) ) for a
> T' La2CuO4 compound.
> I already obtained a reasonable value for U and now, staring from the
> GGA ground state, I'm perturbing onsite magnetizations.
>
> I get rather strange trends that you can find here (links to images at
> the bottom of the page):
>
> http://pad.hdc.pw/p/EPtfu67vWX
>
> An example is also in attachment (I preferred not to add too many/heavy
> attachments to the email. The above link should survive long enough and
> contains the input and output files and other useful informations).
>
> Can someone give me a hint on the (in my opinion) odd results obtained
> for atoms 10, 38, 66 and 94 (they are the atoms of the other, i.e. not
> perturbed, antiferromagnetic sublattice in the same CuO plane).
>
> Should I trust the results obtained starting from those derivatives?
>
> Thanks in advances for your time,
> kind regards,
> Pietro Bonfa'
>
> --
> Pietro Bonfa' - PhD student
> Dipartimento di Fisica e Scienze della Terra "Macedonio Melloni"
> Viale delle Scienze 7A
> 43124 Parma - Italy
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140630/af69eaae/attachment.html
 

[Pw_forum] DFT+U: different oxidation states on the same element (charge ordering)

[Matteo Cococcioni]

Dear Mauro,

one thing I notice is that you are using occupation fixed. is there a
reason for that? this, I think, might actually cause the result you are not
happy about.

Matteo


On Fri, Jun 6, 2014 at 4:39 PM, Mauro Sgroi 
wrote:

> Dear all,
> I'm trying to study the phase separation in LixFePO4 using DFT+U.
> The reference article that I'm using is PRB 69, 201101 (R) 2004, "Phase
> separation in LixFePO4 induced by correlation effects, Zhou et al.
>
> The authors compare, using VASP, standard DFT with DFT+U and obtain the
> correct description of the material with the latter approach. In particular
> they found that is possible to describe the formation of two type of ion,
> Fe2+ and Fe3+, according to to the different position in the unit cell in
> the partially lithiated structures. With GGA all Fe ions have the same
> occupancies, regardless the position in the cell and the fact that they are
> more or less near a lithium ion.
> To obtain this result with DFT+U they had to force the breaking of the
> symmetry of the structure and, I imagine, they set the initial occupations
> in some way to force the desired electronic configuration.
>
> I'm trying to do the same, differentiating the Fe atoms, breaking the
> symmetry and using starting_ns_eigenvalue to force the initial occupations.
> My problem is that at the end of the calculation I got always the same
> occupations on the 4 Fe atoms in the structure (more or less, the
> difference could be 0.3 electrons).
>
> I'm using lda_plus_u_kind=0, but also using the other approach was not
> beneficial.
>
> My input file is below.
> Have you any suggestion?
>
> Thanks a lot in advance and best regards,
> Mauro Sgroi.
>
> &control
> calculation='scf',
> pseudo_dir = "/usr2/sgroi/DATABASE/ESPRESSO",
> prefix='lifepo4_scfU',
> outdir='/home/dati/espresso/temp',
>  /
>  &system
> ibrav=8, celldm(1)=19.748515, celldm(2)=0.586193, celldm(3)=0.441599,
> nat=27, ntyp=5, nosym=.true.
> ecutwfc=40, ecutrho=400, nbnd=130, occupations='fixed',  nspin=2,
> tot_magnetization=17,
> lda_plus_u=.true., Hubbard_U(2)=4., Hubbard_U(3)=4.475,
> starting_ns_eigenvalue(5,2,2)=0,
> starting_ns_eigenvalue(4,2,2)=0,
> starting_ns_eigenvalue(3,2,2)=0,
> starting_ns_eigenvalue(2,2,2)=0,
> starting_ns_eigenvalue(1,2,2)=0,
> starting_ns_eigenvalue(5,2,3)=1,
> starting_ns_eigenvalue(4,2,3)=0,
> starting_ns_eigenvalue(3,2,3)=0,
> starting_ns_eigenvalue(2,2,3)=0,
> starting_ns_eigenvalue(1,2,3)=0
>  /
>  &electrons
>  conv_thr=1.0d-8, electron_maxstep=100, mixing_beta=0.5
>  /
>
> ATOMIC_SPECIES
>  Li 6.941   Li.pbe-s-van_ak.UPF
>  Fe1 55.847  Fe.pbe-sp-van_ak.UPF
>  Fe2 55.847  Fe.pbe-sp-van_ak.UPF
>  P  15.9994 P.pbe-van_ak.UPF
>  O  30.9737 O.pbe-van_ak.UPF
>
> ATOMIC_POSITIONS {crystal}
> Fe1  0.281537138   0.25000   0.9818512061   0   1
> P0.103893879   0.25000   0.4155869701   0   1
> O0.119764467   0.25000   0.7441647381   0   1
> O0.447356144   0.25000   0.2012577561   0   1
> O0.187375840   0.060350405   0.283173864
> Li   0.5   0.0   0.50   0   0
> Fe2  0.211199573   0.75000   0.4746320771   0   1
> P0.405092969   0.75000   0.9225668011   0   1
> O0.401164833   0.75000   0.2515054451   0   1
> O0.041727760   0.75000   0.6862072161   0   1
> O0.336134397   0.956851552   0.790300073
> Li   0.0   0.5   0.00   0   0
> Fe2  0.719627852   0.75000   0.0204225221   0   1
> P0.902369089   0.75000   0.5757736351   0   1
> O0.896492242   0.75000   0.2469824661   0   1
> O0.540334658   0.75000   0.7909135651   0   1
> O0.840097513   0.539754373   0.720678002
> Li   0.5   0.5   0.50   0   0
> Fe2  0.786894270   0.25000   0.5252387321   0   1
> P0.588956858   0.25000   0.0788321901   0   1
> O0.587126133   0.25000   0.7494586611   0   1
> O0.966454798   0.25000   0.3152301911   0   1
> O0.654364669   0.453679217   0.216461848
> O0.822813149   0.944845411   0.700568536
> O0.653714964   0.047069624   0.216100948
> O0.172021112   0.453011228   0.263457462
> O0.335493673   0.543326856   0.788919121
>
> K_POINTS {automatic}
> 2 4 8 1 1 1
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140606/28eb9090/attachment.html
 

[Pw_forum] Fwd: Full LDA+U calculation on orbitals with different orbital angular momentum l

[Matteo Cococcioni]

Dear Simone and Giuseppe,

yes I can confirm that the +U+V code should become available soon. We are
(still) working on the porting but it should not take too long.

Best,

Matteo




On Thu, Jun 5, 2014 at 6:10 PM, Giuseppe Mattioli <
giuseppe.mattioli at ism.cnr.it> wrote:

>
> Dear Simone
> AFAIK the DFT+U+V method (which permits to apply different U corrections
> on different l channels, see, e.g., Himmetoglu, et al.; Int. J. Quantum
> Chem.
> 2014, 114, 14) should be available soon. Maybe Nicola and Matteo can
> provide better information, if they read this post...
> HTH
> Giuseppe
>
> On Wednesday 04 June 2014 16:30:35 simone marocchi wrote:
> > Dear QE users,
> >I am studying an organic complex with rare earth
> > metals (only collinear case, without spin-orbit coupling at the moment).
> > Some articles, as for example:
> >
> > PRB 75, 045114 (2007)
> > ACS Nano, 2014, 8 (5), pp 4662?4671
> >
> > indicate that for a correct description of the rare-earth compounds
> > could be necessary to apply the Hubbard-U corrections both on the f and
> > d electrons of the same atom. If I have understood correctly, now the
> pw.x
> > code can apply
> > the Hubbard correction only on the electrons with the maximum l of each
> > atomic species (for example, in the rare-earths case the f electrons)
> >
> > In my output is written the line
> >
> > "full LDA+U calculation, Hubbard_lmax = 3"
> >
> > I would like to know if it is possible to modify the code in order to
> > enable the Hubbard corrections separately, both on the d and f electrons
> > (with different values of U and J, overall 4 parameters).
> >
> > Approximately, how much effort would require such change ?
> >
> >
> > Thanks for any help,
> > Regards
> >
> > --
> > Simone Marocchi
> >
> > S3 Center, Istituto Nanoscienze, CNR
> > via Campi 213/A, 41125, Modena, Italy
> > Tel: +39 0592055585;  Skype: jacobi84
> > URL: http://www.nano.cnr.it
>
>
> 
> - Article premier - Les hommes naissent et demeurent
> libres et ?gaux en droits. Les distinctions sociales
> ne peuvent ?tre fond?es que sur l'utilit? commune
> - Article 2 - Le but de toute association politique
> est la conservation des droits naturels et
> imprescriptibles de l'homme. Ces droits sont la libert?,
> la propri?t?, la s?ret? et la r?sistance ? l'oppression.
> 
>
>Giuseppe Mattioli
>CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
>v. Salaria Km 29,300 - C.P. 10
>I 00015 - Monterotondo Stazione (RM)
>Tel + 39 06 90672836 - Fax +39 06 90672316
>E-mail: 
>http://www.ism.cnr.it/english/staff/mattiolig
>ResearcherID: F-6308-2012
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140605/9f5a293d/attachment.html
 

[Pw_forum] resp_mat.f90

[Matteo Cococcioni]

Dear Tommaso,

it should be in the tar file you can download that contains the examples to
run.

best,

Matteo


On Thu, May 29, 2014 at 10:58 AM, Tommaso Francese <
neutrinofrancese at gmail.com> wrote:

> Dear all QE users,
> shall i ask you where i can find the reps_mat.f90 script exactly and all
> the script used in
> http://media.quantum-espresso.org/santa_barbara_2009_07/slides-exercices/Handson_ldau.pdf
>  ?
> Thanks in advance,
> Tommaso
> Universit? C? Foscari of Venice
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140529/489e2b1d/attachment.html
 

[Pw_forum] multiples site Hubbard U

[Matteo Cococcioni]

Dear Tommaso,

the same supercell is good for both. You can calculate the U for both
atomic species at the same time simply including both responses in the same
response matrices.

hope this helps.

Matteo


On Wed, May 28, 2014 at 11:47 AM, Tommaso Francese <
neutrinofrancese at gmail.com> wrote:

> Dear all,
> i?m working on a Yttria doped Zirconia, YSZ. I have understood how to
> calculate the U values for a single site, but how can i calculate the U
> values for both the transition metal inside the same structure, e.g. Zr and
> Y in YSZ structure? Do i have to build a supercell even in this case?
> Thanks in advance,
> Tommaso Francese.
> Universit? C? Foscari of Venice.
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140528/918d1aa2/attachment.html
 

[Pw_forum] Eigenvectors in a LDA+U calculation

[Matteo Cococcioni]

Dear Juan

I will try to answer below.


On Thu, May 22, 2014 at 7:13 PM, Juan J. Mel?ndez  wrote:

>   Dear all:
>
> I am playing with the examples for LDA+U. I think that understand that the
> eigenvalues and eigenvectors refer to the occupation matrix, which is
> calculated from the projections onto the proper states of the atom for
> which U correction is to be applied. However, there are two issues which
> are confusing to me:
>
> 1) If I diagonalize occupation matrix externally to QE, I do get the same
> eigenvalues, but quite different eigenvectors, beyond numerical errors, I
> think. Could anybody explain to my why does this happen?
>


Maybe you have some degeneracies? If so, any linear combination of
eigenvectors corresponding to the same eigenvalue, is also an eigenvector
for the same eigenvalue. I believe that diagonalization routines always
provide orthonormal eigenvectors but in the eigenspace of degenerate
eigenvalues the phase is arbitrary and can change with the specific
routine, machine, compiler, etc.




>
> 2) Suppose that I need to use the ?starting_ns_eigenvalue? option to
> correct unreallistic occupations. For that, I have a look at the
> eigenvalues of the occupation matrix at convergence. However, since the
> occupation matrix changes during the calculation (because the d states,
> say, may mix together), the eigenvectors also do. It means that, despite I
> may know which occupation is unphysical at convergence, I cannot know what
> was the corresponding eigenvalue at the first iteration. Am I right? If so,
> how can I apply ?starting_ns_eigenvalue? correctly?
>


you can try to restart the calculation from the one that produces the
occupation matrix you don't like, having the code reading the potential
from it. It should read also the occupations in this case. However setting
starting_ns_eigenvalue might not be effective in this case because in
electrons.f90 the code is does not allow you to change the occupations if
you are reading them from file.
Anyway, if you know the eigenvector you want to change the occupation of,
and that eigenvector appears also after the first iteration of the scf
cycle, then you are safe. keep in mind that starting_ns_eigenvalue changes
the occupation matrix eigenvalues only after the first iteration.

regards,

Matteo



>
> Thanks in advance.
>
> Juanjo
>
> Juan J. Mel?ndez
> Associate Professor
> Department of Physics ? University of Extremadura
> Avda. de Elvas, s/n 06006 Badajoz (Spain)
> Phone: +34 924 28 96 55
> Fax: +34 924 28 96 51
> Email: melendez at unex.es
> Web: http://materiales.unex.es/miembros/personal/jj-melendez/Index.html
>
>
> --
>
>
> Este mensaje no contiene virus ni malware porque la protecci?n de avast!
> Antivirus  est? activa.
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140522/ff1e3f80/attachment.html
 

[Pw_forum] Hubbard U

[Matteo Cococcioni]

Dear Tommaso,

see below.

On Fri, May 16, 2014 at 10:40 AM, Tommaso Francese <
neutrinofrancese at gmail.com> wrote:

> Dear all,
>  as you suggested, i try to follow your tutorial for the Hubbard U
> coefficients determination, but i have some practical difficulties.
>
> Summarizing, i proceded as follow:
>
> step 1)?> i have done a simple SCF with very low coefficients for
> Hubbard_U1 and Hubbard_U2, enabling the wavefunction separate collection
> (wf_collect) ;
>

I don't think wf_collect is necessary. should not be harmful either


> step 2)?> i have performed some SCF, restarting from the charge file
> stored previously,  introducing some fluctuation values in Hubbard_alpha
> (?), is it correct?
>
>
right.


> the problem is at this point: do i need to rename every scf-file in which
> i performed a different perturbation?



yes, otherwise you overwrite them each time. or you can redirect them to
different (properly named) directories.



> How can i, in the next step, ?recall? the different perturbation that i
> performed previously?
>
>
what do you exactly mean by "recall"? do you have difficulties in
recognizing outputs corresponding to different alphas? then see the naming
problem at the previous point.


> At this point is obvious that i don?t know also how to calculate the
> response functions and so, obtaining the Hubbard U coefficient.
>
>
this is what the tutorial is for. were you able to follow the instructions
to the end? Besides the one from the Santa Barbar school there is also
another one from a nother school in 2012 at Penn State. Maybe that is
better?

best,

Matteo




> Can someone help me?
> Thanks a lot,
> Tommaso,
> Universit? C? Foscari of Venice
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140516/062301cb/attachment.html
 

[Pw_forum] Hubbard coefficients

[Matteo Cococcioni]

Hi Tommaso,

for every perturbation the run should restart from the potential (and
wavefunctions) of the uperturbed run. So you need to save the scratch
directory of the latter and copy it to the one used by the perturbed run
before each calculation. This should be evident from the tutorial files.
Also make sure that diago_thr_init (the threshold for the diagonalization
of the Hamiltonian at each step) is set equal to the value it had at the
last iteration of the unperturbed run, so that the diagonalization at the
first iteration of the perturbed run is equally ccurate. Hope this is not
confusing.

best,

Matteo




On Thu, May 15, 2014 at 11:16 PM, Tommy  wrote:

> Thanks to both Giuseppe Mattioli and Pang Gui for their help!!!
> However, I need to ask one more question about the process for obtaining
> Hubbard coefficients: I follow the tutorials posted with the links, but a
> thing wasn't clear to me. After scf simple calculation, I need to "perturb"
> the system in a range between -0.1 & 0.1 eV. But: do i need to save a file
> for every perturbation induced to the system?
> How can i set to QE to take every previous result and compute the U term?
> Be patient, but I'm alone and i trying to do the best for my thesis!!!
> Best regards,
> Tommaso.
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140516/ddbcb0ae/attachment.html
 

[Pw_forum] magnetic moment with LDA+U

[Matteo Cococcioni]

Hi,

they should be in flib. Otherwise try this:
find ./* |grep tabd

Matteo


On Mon, May 12, 2014 at 6:50 PM,  wrote:

> Dear all
>
> I use QE 5.0.1 to calculate the electronic property of Silicine. and
> then I want calculate the magnetic property of ribbon of Silicine with
> LSDA. but I can not find the magnetic moment of every atom of Si. I just
> find the total magnetic moment and absolute magnetic moment. my question is
> that how do I find the magnetic moment of every atom under LSDA
> calculation?
>
> the another question is about the LDA+U calculation. I don't find magnetic
> moment on atom Si, so I use LDA+U to calculate the ribbon of Silicne. but I
> can't plus U on Si. because the Si is not on the list which we can plus U.
> I read userguide, that we can modify the set_hubbard_l.f90 and tabd.f90.
> but I don't find the set_hubbard_l.90 in the directory  PW/src. so that I
> can't modify the file. and then I still can not calculate the LDA+U on Si.
> So which file should be modified and add Si on the list like O and N?
>
> however, we often calculate the magnetic property of material. and how to
> find the spin moment and orbital moment in calculation?
>
>
>
> thank you very much!
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140512/d152a8bc/attachment.html
 

[Pw_forum] Hubbard U Calculation for Hematite

[Matteo Cococcioni]

Dear Sai,

also make sure that the convergence threshold for the first iteration of
the perturbed run is equal to the one from the last iteration of the
unperturbed calculation.

Matteo


On Thu, May 8, 2014 at 9:28 AM, Matteo Cococcioni  wrote:

> Dear Sai,
>
> your figures show that the variations are actually very small and possibly
> within the numerical errors these quantities are affected by. I would
> certainly try to use larger ranges for the perturbation (e.g., from -0.1 to
> 0.1).
>
> best,
>
> Matteo
>
>
> On Wed, May 7, 2014 at 5:07 PM, Sai Kumar Ramadugu  gmail.com>wrote:
>
>> Dear Pietro:
>>
>> My calculations use a unit cell of Fe2O3. Currently I am trying to
>> optimize 2x1 and 2x2 supercells. Once I have the optimized structure, I
>> want redo the linear response calculations.
>>
>> Dear Matteo:
>>
>> The deviations are smaller. For the case of intersection at 0.0, I have
>> very small range from 0.1 to 0.00025 for the difference between the
>> occupations at alpha=0.0 for bare and scf converged responses.
>>
>> About linearity, I have attached two figures for the response of atom 5
>> (Fe) with respect to the perturbed atom (Fe) at the origin and atom 6 (Fe)
>> with respect to the perturbed atom (Fe) at the origin.
>> The alpha values for these two graphs are -0.01, 0.0 and +0.01.
>> The response of atom 5 with perturbed atom does intersect (not at 0.0)
>> but for the response of atom 6, the two lines do not intersect.
>>
>> Would you suggest to use larger values of alpha (close to 0.1) or use a
>> super-cell for the calculations?
>>
>> Thanks very much for the time and help.
>> Sai
>>
>>
>> On Wed, May 7, 2014 at 7:59 AM, Matteo Cococcioni  wrote:
>>
>>> Dear Sai Kumar Ramadug,
>>>
>>> just another idea: how wide are the deviations from linearity? on-site
>>> occupations are difficult to converge beyond the 3rd digit. Sometimes, when
>>> they are minimally affected by the perturbation, their variation can be
>>> within numerical noise.
>>>
>>> regards,
>>>
>>> Matteo
>>>
>>>
>>>
>>>
>>> On Wed, May 7, 2014 at 2:44 PM, Pietro Bonfa' >> > wrote:
>>>
>>>> Dear Sai Kumar Ramadug,
>>>>
>>>> I can comment only on the sentence below:
>>>>
>>>> On 05/06/2014 05:47 PM, Sai Kumar Ramadugu wrote:
>>>> > The problem I am having as of now is that some of the responses dn0/da
>>>> > and dn/da are not linear and do not intersect at 0.
>>>>
>>>> It happened to me as well. In my case I think that it was due to the
>>>> size of my supercell (i.e. to the spurious perturbation introduced by
>>>> the PBC). With a bigger supercell I obtained reasonable results.
>>>>
>>>> Kind regards,
>>>> Pietro Bonfa'
>>>>
>>>> --
>>>> Pietro Bonfa' - PhD student
>>>> Dipartimento di Fisica e Scienze della Terra "Macedonio Melloni"
>>>> Viale delle Scienze 7A
>>>> 43124 Parma - Italy
>>>> ___
>>>> Pw_forum mailing list
>>>> Pw_forum at pwscf.org
>>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>>
>>>
>>>
>>> ___
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>
>>
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140508/4c551838/attachment.html
 

[Pw_forum] Hubbard U Calculation for Hematite

[Matteo Cococcioni]

Dear Sai,

your figures show that the variations are actually very small and possibly
within the numerical errors these quantities are affected by. I would
certainly try to use larger ranges for the perturbation (e.g., from -0.1 to
0.1).

best,

Matteo


On Wed, May 7, 2014 at 5:07 PM, Sai Kumar Ramadugu wrote:

> Dear Pietro:
>
> My calculations use a unit cell of Fe2O3. Currently I am trying to
> optimize 2x1 and 2x2 supercells. Once I have the optimized structure, I
> want redo the linear response calculations.
>
> Dear Matteo:
>
> The deviations are smaller. For the case of intersection at 0.0, I have
> very small range from 0.1 to 0.00025 for the difference between the
> occupations at alpha=0.0 for bare and scf converged responses.
>
> About linearity, I have attached two figures for the response of atom 5
> (Fe) with respect to the perturbed atom (Fe) at the origin and atom 6 (Fe)
> with respect to the perturbed atom (Fe) at the origin.
> The alpha values for these two graphs are -0.01, 0.0 and +0.01.
> The response of atom 5 with perturbed atom does intersect (not at 0.0) but
> for the response of atom 6, the two lines do not intersect.
>
> Would you suggest to use larger values of alpha (close to 0.1) or use a
> super-cell for the calculations?
>
> Thanks very much for the time and help.
> Sai
>
>
> On Wed, May 7, 2014 at 7:59 AM, Matteo Cococcioni  wrote:
>
>> Dear Sai Kumar Ramadug,
>>
>> just another idea: how wide are the deviations from linearity? on-site
>> occupations are difficult to converge beyond the 3rd digit. Sometimes, when
>> they are minimally affected by the perturbation, their variation can be
>> within numerical noise.
>>
>> regards,
>>
>> Matteo
>>
>>
>>
>>
>> On Wed, May 7, 2014 at 2:44 PM, Pietro Bonfa' > fis.unipr.it>wrote:
>>
>>> Dear Sai Kumar Ramadug,
>>>
>>> I can comment only on the sentence below:
>>>
>>> On 05/06/2014 05:47 PM, Sai Kumar Ramadugu wrote:
>>> > The problem I am having as of now is that some of the responses dn0/da
>>> > and dn/da are not linear and do not intersect at 0.
>>>
>>> It happened to me as well. In my case I think that it was due to the
>>> size of my supercell (i.e. to the spurious perturbation introduced by
>>> the PBC). With a bigger supercell I obtained reasonable results.
>>>
>>> Kind regards,
>>> Pietro Bonfa'
>>>
>>> --
>>> Pietro Bonfa' - PhD student
>>> Dipartimento di Fisica e Scienze della Terra "Macedonio Melloni"
>>> Viale delle Scienze 7A
>>> 43124 Parma - Italy
>>> ___
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum
>>>
>>
>>
>> ___
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140508/7c627b30/attachment.html
 

[Pw_forum] Hubbard U Calculation for Hematite

[Matteo Cococcioni]

Dear Sai Kumar Ramadug,

just another idea: how wide are the deviations from linearity? on-site
occupations are difficult to converge beyond the 3rd digit. Sometimes, when
they are minimally affected by the perturbation, their variation can be
within numerical noise.

regards,

Matteo




On Wed, May 7, 2014 at 2:44 PM, Pietro Bonfa' wrote:

> Dear Sai Kumar Ramadug,
>
> I can comment only on the sentence below:
>
> On 05/06/2014 05:47 PM, Sai Kumar Ramadugu wrote:
> > The problem I am having as of now is that some of the responses dn0/da
> > and dn/da are not linear and do not intersect at 0.
>
> It happened to me as well. In my case I think that it was due to the
> size of my supercell (i.e. to the spurious perturbation introduced by
> the PBC). With a bigger supercell I obtained reasonable results.
>
> Kind regards,
> Pietro Bonfa'
>
> --
> Pietro Bonfa' - PhD student
> Dipartimento di Fisica e Scienze della Terra "Macedonio Melloni"
> Viale delle Scienze 7A
> 43124 Parma - Italy
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140507/befe001f/attachment.html
 

[Pw_forum] "DFT+U"

[Matteo Cococcioni]

Dear Francesca,

there are also some tutorials on the topics linked in the webpage of QE.
Probably it's worth you give them a look and try to run them in order to
get familiar with the input (and with the output).

best,

Matteo




On Thu, Apr 24, 2014 at 2:11 PM, francesca costanzo wrote:

>
> Dear all,
> I have a question concerning DFT+U approach in PW,
> according to the linear response theory (Ref. PRB, 67, 153106, 2003).
> I would like to set in my input for the b-NiOOH structure,
> the value of U-J effective of 5.5 for Ni.
>
> If I understand well, I should set in the
> &system section
> the lda_plus_u = .true.,
>  U_projection_type = 'atomic',
>
> and how I can set U-J effective=5.5 eV?
>
> I got confused from all the keywords in the input file descriptions.
>
> thank you in advance for your help.
>
>  Francesca
>
> -
> Francesca Costanzo, Ph.D
> Faculty of Science,
> Leiden Institute of Chemistry,
> Theoretical Chemistry
> Gorlaeus Laboratories
> Einsteinweg 55
> 2333 CC Leiden
>
> -
>
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140424/c6232ad8/attachment.html
 

[Pw_forum] difference between DFT+U+J and rotational invariant DFT+U of lda_u_kind =1

[Matteo Cococcioni]

Dear Jia,

see below.

On Wed, Mar 19, 2014 at 4:31 AM, Jia Chen  wrote:

> Dear Prof. Matteo Cococcioni,
>
> Thank you very much for explanation, it helps me a lot. According to the
> document of pw input file, rotational invariant DFT+U is implemented in pw
> now, with lda_u_type=1. I think my input files are correct, when I use
> rotational invariant DFT+U and DFT+U+J you developed.
>
>
our DFT+U+J is the one you get with hubbard_u_kind = 0 and Hubbard_J0 =/= 0.


> I hope you can understand that my hesitation to put data I don't
> understand on a public place. I can describe my problem. It seems to be
> related to the question why U_eff=U-J is valid. I have two spin states of a
> transition-metal ion. As you know, U favours high-spin state, and
> conventional wisdom tells us J should favours high-spin too. It is easy to
> understand why in simplified DFT+U, J does the opposite, since it is just a
> reduction of  U. I expected, by fully rotational invariant DFT+U, J favours
> high-spin energetically. But, in my calculations, rotational invariant
> DFT+U behaves just like the its' simplified version. Only the DFT+U+J
> method shows the right trend.
>
> If DFT+U+J is just a simple version of rotational invariant DFT+U, I still
> don't know why rotational invariant DFT+U fails for this particular
> problem. I also don't think U_eff=U-J has too much physics ground, but, in
> calculations, it seems to be true...  Any comment on this topic is very
> welcome.
>


As I wrote yesterday in my email DFT+U+J0 is NOT a simpler version of the
rotational invariant DFT+U. if you simplify the rotational invariant DFT+U
you obtain the dudarev DFT+U, possibly with U_eff = U-J.

best,

Matteo



>
> Bests
> Jia
>
>
> On Tue, Mar 18, 2014 at 5:39 AM, Matteo Cococcioni  wrote:
>
>>
>> Dear Jia,
>>
>> when we did the work you cite (the PRB paper on CuO) we understood we
>> needed to have explicit magnetic interactions in the +U functional, but we
>> tried to understand if there were simpler ways to add it than using the
>> otationally invariant implementation of DFT+U. On the other hand the
>> simpler version of it by Dudarev et al (PRB 98) was too simple as it
>> reduces the role of J to a mere reduction of the effective U (that is,
>> U_eff = U-J). To be honest, this latter point I have never fully
>> understood: one gets the simpler version of the +U correction by setting J
>> = 0 in the fully rotational one, so I don't see how one could end up with
>> an effective U that is U-J. Anyway, what we tried to do was to re-analyze
>> the approximation the simpler version is based on (in the limit where U_eff
>> does actually result to be equal to U-J) and to check whether or not other
>> terms of the same order were arising. And it seems to us that an extra one
>> needed to be added.
>>
>> I will try to clarify specific questions of yours below.
>>
>>
>> On Tue, Mar 18, 2014 at 3:07 AM, Jia Chen  wrote:
>>
>>> Dear all,
>>>
>>> I am working on molecule with localized d electrons and two different
>>> spin states, especially correlation due to Hund's coupling J at this
>>> moment. I tried the DFT+U+J method (PRB 84, 115108, 2011) implemented in
>>> Quantum Espresso, and found out the J dependence is quite different from
>>> the rotational invariant DFT+U (PRB 52 R5467, 1995).
>>>
>>
>>
>> first of all: make sure you are using Hubbard_J0 (lda_plus_u_kind = 0).
>> the Hubbard_J relates to the non-collinear implementation and I'm not sure
>> what it does in case of nspin = 2. Although I didn't participate to this
>> implementation, I believe that it might reduce to the fully rotational
>> implementation, but I'm not sure and other people can confirm.
>>
>>
>>
>>> I am surprised by the results, because rotational invariant DFT+U has
>>> full coulomb interaction parametrized by Slater integrals, Hund's coupling
>>> J show up in anisotropic and spin polarized interactions. As a model, it
>>> covers both Hund's first and second rule. Theoretically, I don't know
>>> what's missing in this method.
>>>
>>>
>>
>> see above and below.
>>
>>
>>
>>> Apparently, developers of DFT+U+J know how to go beyond rotational
>>> invariant DFT+U. I read the paper, but still don't understand the idea
>>> behind it. I would like to ask two questions:
>>> 1. What is not right in rotational invariant DFT+U, as a Hartree-Fock
>>> level theory regarding J?
>>>
>>
>>
&

[Pw_forum] difference between DFT+U+J and rotational invariant DFT+U of lda_u_kind =1

[Matteo Cococcioni]

Dear Jia,

when we did the work you cite (the PRB paper on CuO) we understood we
needed to have explicit magnetic interactions in the +U functional, but we
tried to understand if there were simpler ways to add it than using the
otationally invariant implementation of DFT+U. On the other hand the
simpler version of it by Dudarev et al (PRB 98) was too simple as it
reduces the role of J to a mere reduction of the effective U (that is,
U_eff = U-J). To be honest, this latter point I have never fully
understood: one gets the simpler version of the +U correction by setting J
= 0 in the fully rotational one, so I don't see how one could end up with
an effective U that is U-J. Anyway, what we tried to do was to re-analyze
the approximation the simpler version is based on (in the limit where U_eff
does actually result to be equal to U-J) and to check whether or not other
terms of the same order were arising. And it seems to us that an extra one
needed to be added.

I will try to clarify specific questions of yours below.


On Tue, Mar 18, 2014 at 3:07 AM, Jia Chen  wrote:

> Dear all,
>
> I am working on molecule with localized d electrons and two different spin
> states, especially correlation due to Hund's coupling J at this moment. I
> tried the DFT+U+J method (PRB 84, 115108, 2011) implemented in Quantum
> Espresso, and found out the J dependence is quite different from the
> rotational invariant DFT+U (PRB 52 R5467, 1995).
>


first of all: make sure you are using Hubbard_J0 (lda_plus_u_kind = 0). the
Hubbard_J relates to the non-collinear implementation and I'm not sure what
it does in case of nspin = 2. Although I didn't participate to this
implementation, I believe that it might reduce to the fully rotational
implementation, but I'm not sure and other people can confirm.



> I am surprised by the results, because rotational invariant DFT+U has full
> coulomb interaction parametrized by Slater integrals, Hund's coupling J
> show up in anisotropic and spin polarized interactions. As a model, it
> covers both Hund's first and second rule. Theoretically, I don't know
> what's missing in this method.
>
>

see above and below.



> Apparently, developers of DFT+U+J know how to go beyond rotational
> invariant DFT+U. I read the paper, but still don't understand the idea
> behind it. I would like to ask two questions:
> 1. What is not right in rotational invariant DFT+U, as a Hartree-Fock
> level theory regarding J?
>


the fact that it is Hartree-Fock level of theory. In fact, as we wrote in
the paper, the extra term we added is beyond HF in the sense that it cannot
be captured supposing that the many-body wave function consists of a single
Slater determinant.



> 2. How DFT+U+J improves rotational invariant DFT+U, just in general?
>


we didn't compare the two. but if you end up doing please report the
results on this forum.

Hope this helps. best,

Matteo



>
> Appreciate your help!
>
> Cheers
> --
> Jia Chen
> Postdoc, Columbia University
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140318/07b4e80a/attachment.html
 

[Pw_forum] LDA+U calculation for La and Sr

[Matteo Cococcioni]

Dear Heng,

I think this is due to the fact that the La pseudopotential you are using
does not have any f state (in fact La has 4f empty).
are you sure you need to have the +U correction on the 4f states?

Best,

Matteo


On Tue, Feb 4, 2014 at 9:33 PM, Heng Luo  wrote:

> Dear All,
>
> I would like to use LDA+U to calculate a system with La and Sr.
> So I need to add hubbard_l value in set_hubbard_l.f90 file.
> Because La is a rare element, so I am trying to set hubbard_l = 3. Then
> when I am trying to run jobs, there is an error said that "offset_atom_wfc,
> wrong offset". It is some error in offset_atom_wfc.f90 file. I don't know
> how to modify it.
>
> Do you have some ideas that how to apply LDA+U for La?
>
> Best regrad
>
> --
> Heng Luo
> Ph.D candidate
> Department of Mechanical Engineering
> 15 Saint Mary's Street, Room 122
> Brookline, Ma 02446
> Boston University
>
> Office: 617-353-8469
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 
Matteo Cococcioni
Department of Chemical Engineering and Materials Science,
University of Minnesota
421 Washington Av. SE
Minneapolis, MN 55455
Tel. +1 612 624 9056Fax +1 612 626 7246
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20140204/04d86462/attachment.html
 

[Pw_forum] Calculation of U for Fe co-existing in two different oxidation state

[Matteo Cococcioni]

Dear Prasenjit

I assume you have already downloaded and got familiar with the tutorial
from the webpage of Quantum Espresso to calculate U. The only tricky part
is that the 3+ and 2+ Fe have to be treated as atoms of different kind
(although associated with the same pseudopotential) and perturbed
independently.

hope this helps.

Matteo


On Fri, Nov 1, 2013 at 7:40 AM, Prasenjit Ghosh wrote:

> Dear all,
>
> I am trying to do some calculations for iron oxide, in which the Fe is
> present in both the oxidation states, +2 and +3. Can any one suggest how to
> determine the value of U for such cases?
>
> With regards,
>
> Prasenjit
>
> --
> PRASENJIT GHOSH,
> IISER Pune,
> First floor, Central Tower, Sai Trinity Building
> Garware Circle, Sutarwadi, Pashan
> Pune, Maharashtra 411021, India
>
> Phone: +91 (20) 2590 8203
> Fax: +91 (20) 2589 9790
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 
Matteo Cococcioni
Department of Chemical Engineering and Materials Science,
University of Minnesota
421 Washington Av. SE
Minneapolis, MN 55455
Tel. +1 612 624 9056Fax +1 612 626 7246
-- next part --
An HTML attachment was scrubbed...
URL: 
http://pwscf.org/pipermail/pw_forum/attachments/20131101/e32a393f/attachment.html
 

[Pw_forum] Electronic entropy

[Matteo Cococcioni]

Dear Nicolas

If you use the smearing=FD the degauss parameter is the electronic
temperature (T) that gives you a measure of the (physical) broadening
of the Fermi distribution function (the deviation from its 0 K step
shape). if you use other smearing schemes degauss still measures the
smearing width of your (generalized) distribution function but does
not correspond exactly to the physical temperature anymore.
Generalized distribution functions (instead of FD) are used for
numerical convenience (i.e. to reduce the dependence of the total
energy on the smearing, particularly useful if you want to recover the
physics at 0 K). Useful reference:
DOI:10.1103/PhysRevB.51.6773
See also refs 16 and 17 quoted therein.

regards,

Matteo




On Wed, Mar 27, 2013 at 3:18 AM, Nicolas FERNANDEZ
 wrote:
> Dear all,
>
> I try to evaluate the electronic entropy contribution to the vacancy 
> formation.
>
> I used smearing with Fermi-Dirac function and a degauss value of 0.01 Ry
>
> A line in the output file look very promising to calculate entropy :
> smearing contrib. (-TS)   =  -0.11576742 Ry
> but I have a doubt about the "T" term.
> It (probably) corresponds to the temperature but the temperature of what?
> What is the temperature unit?
> How to calculate or set it?
> Is my approach correct to evaluate the electronic entropy?
>
> Thank you for your responses.
>
> Best regards,
>
> Nicolas
> PhD student
> Aix-Marseille University
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum



-- 
Matteo Cococcioni
Department of Chemical Engineering and Materials Science,
University of Minnesota
421 Washington Av. SE
Minneapolis, MN 55455
Tel. +1 612 624 9056Fax +1 612 626 7246

[Pw_forum] t2g eg

[Matteo Cococcioni]

Dear Sakhraoui,

eg and t2g are the two groups of states that form when d states split
in a cubic crystal field. you can find this explained in many
condensed matter text books and even a more complete collection of
cases in chemistry text books where ligand field theory is
illustrated.

Matteo


On Tue, Feb 19, 2013 at 8:18 AM, Sakhrawi Taoufek  
wrote:
> dear qe users,
> I found in many references the authors pointed out the eg and t2g band in
> the DOS, and wrote in the text accordingly that it had eg symmetry (or t2g
> symmetry). How do i conclude that just from one Dos?
> Best regards
>
>
> ==
> Sakhraoui TAOUFIK
> PhD student
> LMCN, Monastir, Tunisia
> ==
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum



-- 
Matteo Cococcioni
Department of Chemical Engineering and Materials Science,
University of Minnesota
421 Washington Av. SE
Minneapolis, MN 55455
Tel. +1 612 624 9056Fax +1 612 626 7246