[Pw_forum] Spin Polarization and Relaxation

[Akmal Khan]

Dear QE users and experts,

The Final energy after relaxation with and without
spin polarization is different.It is,a bit, on higher side with spin
polarization. Do we need to include spin polarization during relaxation,?
What is the best approach to proceed?



Thank You.
A.Khan
M.phil Research Student
HU Pakistan.
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[Pw_forum] Spin magnetization

[Andrey Chibisov]

I want to investigate the behavior of the phosphorus spin. I know that three 
methods implemented in Espresso:
1. Spin-polarized calculations (nspin = 2)
2. noncollinear calculations (noncolin)
3. Spin-orbit calculations (lspinorb)
In the first case, the electron spin is described.
Dear colleagues, tell me which spin is described in cases 2 and 3, electron or 
nuclei?

-- 
Best regards,
Andrey Chibisov. Ph.D.
Senior Researcher,
Numerical method of mathematical physics Laboratory,
Computational Center, Russian Academy of Sciences.
Khabarovsk, Russia
Web page: https://www.researchgate.net/profile/A_Chibisov
http://ru.linkedin.com/pub/andrey-chibisov/55/253/986/en
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[Pw_forum] spin-dependent electron-phonon coefficients

[Małgorzata Wawrzyniak-Adamczewska]

Dear QE users and developers, 

I would like to calculate spin-dependent electron-phonon lambda
coefficients (for magnetic molecule). 

So far I succeeded to obtain the non-spin dependent lambdas (using
QE-5-2-1), but this distribution fails to calculate the spin-dependent
one. 

I used US-PAW pseudos. 

Is there any QE distribution with already implemented spin-dependent
el-ph (or lambdas for systems with spin-orbit) ? 

Maybe I should use Norm-Cons pseudos for spin-dependent lambdas? 

Please, give a piece of advice. 

My best regards, 

Malgorzata Wawrzyniak-Adamczewska 

ZSECS Adam Mickiewicz University, Poznan, Poland___
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[Pw_forum] spin-dependent electron-phonon coefficients

[Małgorzata Wawrzyniak-Adamczewska]

Dear QE users and developers, 

I would like to calculate spin-dependent electron-phonon lambda
coefficients (for magnetic molecule). 

So far I succeeded to obtain the non-spin dependent lambdas (using
QE-5-2-1), but this distribution fails to calculate the spin-dependent
one. 

I used US-PAW pseudos. 

Is there any QE distribution with already implemented spin-dependent
el-ph (or lambdas for systems with spin-orbit) ? 

Maybe I should use Norm-Cons pseudos for spin-dependent lambdas? 

Please, give a piece of advice. 

My best regards, 

Malgorzata Wawrzyniak-Adamczewska 

ZSECS Adam Mickiewicz University, Poznan, Poland___
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[Pw_forum] Spin-orbit matrix elements

[Oier Arcelus]

Dear All,


I have a pretty naive question. Is there any way to get spin-orbit coupling 
matrix elements on the basis of bloch orbitals directly? Some sort of 
 ?


Best regards,


Oier.
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Re: [Pw_forum] spin-orbit interaction + pressure

[Максим Арсентьев]

Dear Maksim,

In some extent I satisfied by those curves. Now I need get accurate
calculations of structure, because for this case I have cell volume
different from both those authors and hence mine is mistakenly.
Does my input allow get accurate geometry optimization?

Thanks in advance.


2016-12-02 23:40 GMT+04:00 Maksim Markov :

> Maxim,
>
> Pseudopotential of Mn you use has s and p semicore states in valence.
>
> A brief check of the articles you have attached shows that U_{Fe}
> parameters are slightly different (U_Fe = 5eV in Li et al and U_Fe = 4.5
> eV ).
>
> Li et al used VASP and PAW pseudos from VASP library, while H. Lee et al
> used QE and ultrasoft pseudos. In your place, I would try to use the same
> paratameters as H. Lee and to reproduce their results.
>
> Best regards,
>
> Maxime
>
> > Dear Maxim,
> >
> > I used GGA Mn psp, believe semicore not used often in my case
> (Li2MnSiO4).
> > I used
> > http://www.quantum-espresso.org/wp-content/uploads/upf_
> files/Mn.pbe-sp-van.UPF
> > and the same analogs for Li, Si, O.
> > this is my input
> > And these two papaers with their graphs
> > http://pubs.rsc.org/en/content/articlelanding/2014/
> ta/c3ta14885h#!divAbstract
> > http://pubs.acs.org/doi/abs/10.1021/cm500803e
> >
> > 2016-11-29 12:59 GMT+04:00 Lorenzo Paulatto
> > 
> > :
> >
> >> On Monday, November 28, 2016 11:12:52 PM CET Maksim Markov wrote:
> >> > Dear Maxim,
> >> >
> >> > The results depend on pseudopotential you use. For example, you might
> >> have
> >> > different exchange-correlation parts or include (or not include)
> >> semi-core
> >> > states in valence. In this case it is not surprising that you have
> >> > different
> >> > results.
> >>
> >> Just a little comment on top of what Maxime said. It is unrealistic to
> >> have
> >> very accurate phase diagrams with DFT, for several reason. But in
> >> particular,
> >> the energy scale is quite very wide: 300K correspond to just 0.0005Ry
> >> (0.5
> >> mRy)
> >>
> >>
> >>
> >> --
> >> Dr. Lorenzo Paulatto
> >> IdR @ IMPMC -- CNRS & Université Paris 6
> >> phone: +33 (0)1 44275 084 / skype: paulatz
> >> www:   http://www-int.impmc.upmc.fr/~paulatto/
> >> mail:  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
> >>
> >
> >
> >
> > --
> > Best wishes,
> > Maxim Arsent'ev, Ph.D. (Chemistry)
> > Laboratory of research of nanostructures
> > Institute of Silicate Chemistry of RAS
> > ___
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> > http://pwscf.org/mailman/listinfo/pw_forum
>
>
> Maksim Markov, Doctorant
> Laboratoire des Solides Irradies
> Ecole Polytechnique
>
> Route de Saclay
> 91128 Palaiseau
>
> tel: +33 1 69 33 44 97
>
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-- 
Best wishes,
Maxim Arsent'ev, Ph.D. (Chemistry)
Laboratory of research of nanostructures
Institute of Silicate Chemistry of RAS


Li2MnSiO4 (1).in
Description: Binary data
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Re: [Pw_forum] spin-orbit interaction + pressure

[Maksim Markov]

Maxim,

Pseudopotential of Mn you use has s and p semicore states in valence.

A brief check of the articles you have attached shows that U_{Fe}
parameters are slightly different (U_Fe = 5eV in Li et al and U_Fe = 4.5
eV ).

Li et al used VASP and PAW pseudos from VASP library, while H. Lee et al
used QE and ultrasoft pseudos. In your place, I would try to use the same
paratameters as H. Lee and to reproduce their results.

Best regards,

Maxime

> Dear Maxim,
>
> I used GGA Mn psp, believe semicore not used often in my case (Li2MnSiO4).
> I used
> http://www.quantum-espresso.org/wp-content/uploads/upf_files/Mn.pbe-sp-van.UPF
> and the same analogs for Li, Si, O.
> this is my input
> And these two papaers with their graphs
> http://pubs.rsc.org/en/content/articlelanding/2014/ta/c3ta14885h#!divAbstract
> http://pubs.acs.org/doi/abs/10.1021/cm500803e
>
> 2016-11-29 12:59 GMT+04:00 Lorenzo Paulatto
> 
> :
>
>> On Monday, November 28, 2016 11:12:52 PM CET Maksim Markov wrote:
>> > Dear Maxim,
>> >
>> > The results depend on pseudopotential you use. For example, you might
>> have
>> > different exchange-correlation parts or include (or not include)
>> semi-core
>> > states in valence. In this case it is not surprising that you have
>> > different
>> > results.
>>
>> Just a little comment on top of what Maxime said. It is unrealistic to
>> have
>> very accurate phase diagrams with DFT, for several reason. But in
>> particular,
>> the energy scale is quite very wide: 300K correspond to just 0.0005Ry
>> (0.5
>> mRy)
>>
>>
>>
>> --
>> Dr. Lorenzo Paulatto
>> IdR @ IMPMC -- CNRS & Université Paris 6
>> phone: +33 (0)1 44275 084 / skype: paulatz
>> www:   http://www-int.impmc.upmc.fr/~paulatto/
>> mail:  23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris
>> Cédex 05
>>
>> ___
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>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
>
> --
> Best wishes,
> Maxim Arsent'ev, Ph.D. (Chemistry)
> Laboratory of research of nanostructures
> Institute of Silicate Chemistry of RAS
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Maksim Markov, Doctorant
Laboratoire des Solides Irradies
Ecole Polytechnique

Route de Saclay
91128 Palaiseau

tel: +33 1 69 33 44 97

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[Pw_forum] spin-orbit coupling

[Mortaza Aghtar]

Dear all,

I would like to raise my question since I didn't get any response.
Is there a way to calculate the spin-orbit coupling values for certain
spins?

Best regards,
Mortaza

-- 
Mortaza Aghtar, Ph.D.

Ulm Universität
Institut für Theoretiche Physik
Albert-Einstein-Allee 11
89081 Ulm

Office: 405/O25
Telephone: (+49) 731-50-22905
Group Page: http://qubit-ulm.com/
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Re: [Pw_forum] spin-orbit interaction + pressure

[Lorenzo Paulatto]

On Monday, November 28, 2016 11:12:52 PM CET Maksim Markov wrote:
> Dear Maxim,
> 
> The results depend on pseudopotential you use. For example, you might have
> different exchange-correlation parts or include (or not include) semi-core
> states in valence. In this case it is not surprising that you have
> different
> results.

Just a little comment on top of what Maxime said. It is unrealistic to have 
very accurate phase diagrams with DFT, for several reason. But in particular, 
the energy scale is quite very wide: 300K correspond to just 0.0005Ry (0.5 
mRy)



-- 
Dr. Lorenzo Paulatto 
IdR @ IMPMC -- CNRS & Université Paris 6
phone: +33 (0)1 44275 084 / skype: paulatz
www:   http://www-int.impmc.upmc.fr/~paulatto/
mail:  23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05

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Re: [Pw_forum] spin-orbit interaction + pressure

[Maksim Markov]

Dear Maxim,

The results depend on pseudopotential you use. For example, you might have
different exchange-correlation parts or include (or not include) semi-core
states in valence. In this case it is not surprising that you have
different
results.

Best regards,

Maksim Markov, Doctorant
Laboratoire des Solides Irradies
Ecole Polytechnique

Route de Saclay
91128 Palaiseau

tel: +33 1 69 33 44 97


> Dear Lorenzo,
>
> I have a question too.
> How to get accurate total energy calculations for phase diagrams?
> I have read 2 papers from respective journals dealing with the same object
> but having (!) different results.
> In my calls I have result which is medium between these two papers.
>
> Thank you, Maxim.
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Re: [Pw_forum] spin-orbit interaction + pressure

[Максим Арсентьев]

Dear Lorenzo,

I have a question too.
How to get accurate total energy calculations for phase diagrams?
I have read 2 papers from respective journals dealing with the same object
but having (!) different results.
In my calls I have result which is medium between these two papers.

Thank you, Maxim.
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Re: [Pw_forum] spin-orbit interaction + pressure

[Andrey Chibisov]

Dear Dr. Lorenzo,
Thanks a lot for your comments.

29.11.2016, 00:22, "Lorenzo Paulatto" :
> On Monday, November 28, 2016 11:45:01 PM CET Andrey Chibisov wrote:
>>  Can I use the spin-orbit interaction with pressure?
>
> You can, because the pressur estill exists, but it cannot be computed, hence
> the following limitations apply:
> 1. you won't be able to know how much pressure you are actually applying
> without doing finite difference derivation
> 2. you won't be able to use automatic optimisation of the cell volume (i.e.
> vc-relax)
>
> hth
>
> --
> Dr. Lorenzo Paulatto
> IdR @ IMPMC -- CNRS & Université Paris 6
> phone: +33 (0)1 44275 084 / skype: paulatz
> www: http://www-int.impmc.upmc.fr/~paulatto/
> mail: 23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05
>
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-- 
Best regards,
Andrey Chibisov. Ph.D.
Numerical method of mathematical physics Laboratory,
Computational Center, Russian Academy of Sciences.
Khabarovsk, Russia
Web page: https://www.researchgate.net/profile/A_Chibisov
http://ru.linkedin.com/pub/andrey-chibisov/55/253/986/en
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Re: [Pw_forum] spin-orbit interaction + pressure

[Lorenzo Paulatto]

On Monday, November 28, 2016 11:45:01 PM CET Andrey Chibisov wrote:
> Can I use the spin-orbit interaction with pressure?

You can, because the pressur estill exists, but it cannot be computed, hence 
the following limitations apply:
1. you won't be able to know how much pressure you are actually applying 
without doing finite difference derivation
2. you won't be able to use automatic optimisation of the cell volume (i.e. 
vc-relax)


hth

-- 
Dr. Lorenzo Paulatto 
IdR @ IMPMC -- CNRS & Université Paris 6
phone: +33 (0)1 44275 084 / skype: paulatz
www:   http://www-int.impmc.upmc.fr/~paulatto/
mail:  23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05

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Re: [Pw_forum] spin-orbit interaction + pressure

[Максим Арсентьев]

of course, this is like usual geom. opt. but with pressure


2016-11-28 17:45 GMT+04:00 Andrey Chibisov :

> Dear Colleagues,
> I want to apply a pressure to the silicene. The system relaxes, but the
> pressure tensor is not printed.
> There is a message:
>  Message from routine stres:
>  noncollinear stress + GGA not implemented
> Can I use the spin-orbit interaction with pressure?
>
> --
> Best regards,
> Andrey Chibisov. Ph.D.
> Numerical method of mathematical physics Laboratory,
> Computational Center, Russian Academy of Sciences.
> Khabarovsk, Russia
> Web page: https://www.researchgate.net/profile/A_Chibisov
> http://ru.linkedin.com/pub/andrey-chibisov/55/253/986/en
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-- 
Best wishes,
Maxim Arsent'ev, Ph.D. (Chemistry)
Laboratory of research of nanostructures
Institute of Silicate Chemistry of RAS
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[Pw_forum] spin-orbit interaction + pressure

[Andrey Chibisov]

Dear Colleagues,
I want to apply a pressure to the silicene. The system relaxes, but the 
pressure tensor is not printed.
There is a message:
 Message from routine stres:
 noncollinear stress + GGA not implemented
Can I use the spin-orbit interaction with pressure?

-- 
Best regards,
Andrey Chibisov. Ph.D.
Numerical method of mathematical physics Laboratory,
Computational Center, Russian Academy of Sciences.
Khabarovsk, Russia
Web page: https://www.researchgate.net/profile/A_Chibisov
http://ru.linkedin.com/pub/andrey-chibisov/55/253/986/en
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Re: [Pw_forum] SPIN

[Giovanni Cantele]

the starting magnetisation is provided as input variable, as detailed here:
http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#idm6316208 

and is needed to break the symmetry and allow pw.x to search for a magnetic 
solution with
energy lower that the non magnetic one, if it exists. So, even in absence of 
spin-orbit coupling,
if you want to study a magnetic ground state of a certain material, you have to 
provide it in input
to trigger the spin-polarised calculation.

The total magnetisation is instead used to impose a specific magnetisation on 
your system:
http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#idm6318192 

instead of allowing pw.x to determine it during the self-consistent cycle. Of 
course, if you
impose something it is not guaranteed that you are studying the lowest energy 
configuration.

Giovanni

> On 17 Nov 2016, at 14:24, ashkan shekaari  wrote:
> 
> Dear Giovanni Cantele,
> 
> Thank you so much for the detailed response. As my last question, what is the 
> exact difference between starting magnetization and total magnetization?
> 
> --
> Regards,
> Ashkan Shekaari
> Plasma Physics Research Center
> Science and Research Branch
> I A U, 14778-93855 Tehran, Iran.
> 
> On Thu, Nov 17, 2016 at 2:16 PM, Giovanni Cantele 
> mailto:giovanni.cant...@spin.cnr.it>> wrote:
> No, it is not necessary if you do not expect that the system under study has 
> a magnetisation.
> See here:
> http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide/node10.html#SECTION00043030
>  
> 
> 
> In practice, for solids where NO internal or external magnetic field is not 
> present,
> time-reversal symmetry applies. This has the consequence that
> 
> E(k,up) = E(-k,down)
> 
> so for a non-magnetic solid, even in the presence of spin-orbit coupling, it 
> is possible that the spin-up and spin-down
> densities are the same and the total magnetisation zero. Non-magnetic solids 
> then can divided into
> systems with (spatial) inversion symmetry and systems where this symmetry 
> does not apply.
> 
> The former have the additional constraint that E(k, any_spin)=E(-k,any_spin) 
> that, combined with the previous equation,
> produces double SPIN degenerate bands (so each state AT GIVEN is at least 
> double degenerate). Germanium is an example.
> 
> The latter show a lifting of this double SPIN degeneracy, like in the case of 
> GaAs. The spin degeneracy is recovered ONLY
> for those k-points for which k and -k are equivalent (thus differing by only 
> a reciprocal lattice vector). Gamma point is an example.
> 
> Giovanni
> 
> 
>> On 16 Nov 2016, at 22:17, ashkan shekaari > > wrote:
>> 
>> Dear experts,
>> 
>> Is starting magnetization necessary to have a full spin-orbit coupling?
>> 
>> What value should it take on?
>> --
>> Regards,
>> Ashkan Shekaari
>> Plasma Physics Research Center
>> Science and Research Branch
>> I A U, 14778-93855 Tehran, Iran.
>> ___
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>> 
> -- 
> 
> Giovanni Cantele, PhD
> CNR-SPIN
> c/o Dipartimento di Fisica
> Universita' di Napoli "Federico II"
> Complesso Universitario M. S. Angelo - Ed. 6
> Via Cintia, I-80126, Napoli, Italy
> e-mail: giovanni.cant...@spin.cnr.it 
> Phone: +39 081 676910
> Skype contact: giocan74
> 
> ResearcherID: http://www.researcherid.com/rid/A-1951-2009 
> 
> Web page: http://people.na.infn.it/~cantele 
> 
> 
> 
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> 
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-- 

Giovanni Cantele, PhD
CNR-SPIN
c/o Dipartimento di Fisica
Universita' di Napoli "Federico II"
Complesso Universitario M. S. Angelo - Ed. 6
Via Cintia, I-80126, Napoli, Italy
e-mail: giovanni.cant...@spin.cnr.it
Phone: +39 081 676910
Skype contact: giocan74

ResearcherID: http://www.researcherid.com/rid/A-1951-2009
Web page: http://people.na.infn.it/~cantele

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Re: [Pw_forum] SPIN

[ashkan shekaari]

Dear Giovanni Cantele,

Thank you so much for the detailed response. As my last question, what is
the exact difference between starting magnetization and total magnetization?

*--*
*Regards,*
*Ashkan Shekaari*
*Plasma Physics Research Center*
*Science and Research Branch*
*I A U, 14778-93855 Tehran, Iran.*

On Thu, Nov 17, 2016 at 2:16 PM, Giovanni Cantele <
giovanni.cant...@spin.cnr.it> wrote:

> No, it is not necessary if you do not expect that the system under study
> has a magnetisation.
> See here:
> http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_
> user_guide/node10.html#SECTION00043030
>
> In practice, for solids where NO internal or external magnetic field is
> not present,
> time-reversal symmetry applies. This has the consequence that
>
> E(k,up) = E(-k,down)
>
> so for a non-magnetic solid, even in the presence of spin-orbit coupling,
> it is possible that the spin-up and spin-down
> densities are the same and the total magnetisation zero. Non-magnetic
> solids then can divided into
> systems with (spatial) inversion symmetry and systems where this symmetry
> does not apply.
>
> The former have the additional constraint that E(k,
> any_spin)=E(-k,any_spin) that, combined with the previous equation,
> produces double SPIN degenerate bands (so each state AT GIVEN is at least
> double degenerate). Germanium is an example.
>
> The latter show a lifting of this double SPIN degeneracy, like in the case
> of GaAs. The spin degeneracy is recovered ONLY
> for those k-points for which k and -k are equivalent (thus differing by
> only a reciprocal lattice vector). Gamma point is an example.
>
> Giovanni
>
>
> On 16 Nov 2016, at 22:17, ashkan shekaari  wrote:
>
> Dear experts,
>
> Is starting magnetization necessary to have a full spin-orbit coupling?
>
> What value should it take on?
> *--*
> *Regards,*
> *Ashkan Shekaari*
> *Plasma Physics Research Center*
> *Science and Research Branch*
> *I A U, 14778-93855 Tehran, Iran.*
> ___
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>
>
> --
>
> Giovanni Cantele, PhD
> CNR-SPIN
> c/o Dipartimento di Fisica
> Universita' di Napoli "Federico II"
> Complesso Universitario M. S. Angelo - Ed. 6
> Via Cintia, I-80126, Napoli, Italy
> e-mail: giovanni.cant...@spin.cnr.it
> Phone: +39 081 676910
> Skype contact: giocan74
>
> ResearcherID: http://www.researcherid.com/rid/A-1951-2009
> Web page: http://people.na.infn.it/~cantele
>
>
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Re: [Pw_forum] SPIN

[Giovanni Cantele]

No, it is not necessary if you do not expect that the system under study has a 
magnetisation.
See here:
http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide/node10.html#SECTION00043030
 


In practice, for solids where NO internal or external magnetic field is not 
present,
time-reversal symmetry applies. This has the consequence that

E(k,up) = E(-k,down)

so for a non-magnetic solid, even in the presence of spin-orbit coupling, it is 
possible that the spin-up and spin-down
densities are the same and the total magnetisation zero. Non-magnetic solids 
then can divided into
systems with (spatial) inversion symmetry and systems where this symmetry does 
not apply.

The former have the additional constraint that E(k, any_spin)=E(-k,any_spin) 
that, combined with the previous equation,
produces double SPIN degenerate bands (so each state AT GIVEN is at least 
double degenerate). Germanium is an example.

The latter show a lifting of this double SPIN degeneracy, like in the case of 
GaAs. The spin degeneracy is recovered ONLY
for those k-points for which k and -k are equivalent (thus differing by only a 
reciprocal lattice vector). Gamma point is an example.

Giovanni


> On 16 Nov 2016, at 22:17, ashkan shekaari  wrote:
> 
> Dear experts,
> 
> Is starting magnetization necessary to have a full spin-orbit coupling?
> 
> What value should it take on?
> --
> Regards,
> Ashkan Shekaari
> Plasma Physics Research Center
> Science and Research Branch
> I A U, 14778-93855 Tehran, Iran.
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CNR-SPIN
c/o Dipartimento di Fisica
Universita' di Napoli "Federico II"
Complesso Universitario M. S. Angelo - Ed. 6
Via Cintia, I-80126, Napoli, Italy
e-mail: giovanni.cant...@spin.cnr.it
Phone: +39 081 676910
Skype contact: giocan74

ResearcherID: http://www.researcherid.com/rid/A-1951-2009
Web page: http://people.na.infn.it/~cantele

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Re: [Pw_forum] SPIN

[Lorenzo Paulatto]

On Thursday, November 17, 2016 12:47:16 AM CET ashkan shekaari wrote:
> Dear experts,
> 
> Is starting magnetization necessary to have a full spin-orbit coupling?
> 
> What value should it take on?

I'm not 100% sure, normally you need a starting_magnetization to break the 
initial time reversal symmetry and allow the system to polarize, however if 
I'm not wrong, this is breaking of symmetry is always present when using full-
relativistic pseudopotentials with spin orbit coupling (are you?)

Anyway, it is just a starting value and the system *should* converge to the 
the same ground state regardless of the choice. Just set it to some small 
numbe, i.e. 0.01 and have a try.

Not that starting_magnetization is defined per atomic *species* not per atom, 
and it goes from 0 (atom is non-magnetic) to 1 (the atom is as polarized as 
possible in its isolated atom configuration).

I try to clarify with an example.  Let's say you have an Oxygen atom, with 
valence configuration 2s2 2p4. If you set starting_magnetization=0, then the 2 
2s electrons will be one spin up and one spin down, the 4 2p electrons will be 
2 spin up and 2 spin down, total=0. If you set starting_magnetization=1, then 
the 2s electrons will still be one up and one down, because there is no other 
way to do it, but the 2p electrons will be 3 spin up and 1 spin down, for a 
total magnetic moment of 2 Bohr magnetons

hth



-- 
Dr. Lorenzo Paulatto 
IdR @ IMPMC -- CNRS & Université Paris 6
phone: +33 (0)1 44275 084 / skype: paulatz
www:   http://www-int.impmc.upmc.fr/~paulatto/
mail:  23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05

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[Pw_forum] SPIN

[ashkan shekaari]

Dear experts,

Is starting magnetization necessary to have a full spin-orbit coupling?

What value should it take on?
*--*
*Regards,*
*Ashkan Shekaari*
*Plasma Physics Research Center*
*Science and Research Branch*
*I A U, 14778-93855 Tehran, Iran.*
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[Pw_forum] spin-orbit matrix elements

[Mortaza Aghtar]

Dear QE community,

I am not sure whether my question is correct but:

Is it possible to print out the terms of* < i | Hso | j > *, the matrix
elements of spin-orbit Hamiltonian. I think the sum of diagonal values is
what arises in the total energy as SOC but I am also interested in the
off-diagonal terms which reflect the spin-orbit couplings of transition
between two states.


All the best,
M. Aghtar

--

Mortaza Aghtar, Ph.D. of Physics

Ulm Universität
Institut für Theoretiche Physik
Albert-Einstein-Allee 11
89081 Ulm, Germany
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[Pw_forum] Spin calculation.

[Himani Mishra]

Dear Sir,
I want to calculate full spinor wave functions of my system and the
calculation should be non collinear. Tell me a way to do this in pwscf. I
also need to give vander waals corrections.
I tried doing this but not able to give both spin effects and van der waals
correction at the same time.

Regards,
Himani Mishra
RSE2016002
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[Pw_forum] Spin-Orbit coupling on Bi iron garnet

[Federico Iori]

Dear PW'ers 

I have a problem in converging a calculation with SO coupling on a large system 
of Bi3Fe5O12 (BIG).. (nomen omen). 

I am doing a calculation with addiction of Hubbard U on Fe d- orbitals, and SO 
on Bi atoms only 
thus full relativistic pseudo on Bi and scalar relativistic pseudos on Fe and O 
species. 

Naively I tried differents solutions: 

1. SCF SO + U calculation from scratch with 
2. SCF SO+U calculation from a previous spin polarized GGA+U calculation 
(nspin=2, startingpot=file to read the precalculated density). 


In all the cases my total energy after even 1000 electronic steps is still 
oscillating and not converging at all, as the magnetic moments thou. 
I tried to reduce the mixing_beta even to 10^-5 without any improvement as 
well. 

BTW, I did a similar calculation on a similar system, YIG substituting the Bi 
with the Y without encoutering any issues in the SO calculation. 



For that I am asking you some help because I do not understand if I am doing 
something really wrong or not. 


I attach the input file in the mail. 

Many thanks for the support. 
Federico 


Federico IORI 
Marie Curie Fellow 
Laboratoire de Physique des Solides 
Bâtiment 510 - Rue André Rivière 
91400 Orsay 




pw.in
Description: Binary data
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Re: [Pw_forum] Spin orbit coupling

[Giuseppe Mattioli]

Dear user
First of all sign your posts with name and scientific affiliation, please.

When you start using a new code you should read the documentation  
before computing.

Apart from the general documentation, there are several examples  
embedded in the QE distribution. Look into

your-path-to-QE/PW/examples/README

and you will find

example07:
 This example shows how to use pw.x to calculate the total energy
 and the band structure of fcc-Pt with a fully relativistic US-PP
 which includes spin-orbit effects.

Then look into the example directory

your-path-to-QE/PW/examples/example07/README

REFERENCES:

A. Dal Corso and A. Mosca Conte,
Spin-orbit coupling with ultrasoft pseudopotentials: application to Au and Pt,
Phys. Rev. B 71, 115106 (2005)

A. Dal Corso,
Projector augmented-wave method with spin-orbit coupling: applications to
simple solids and zincblende-type semiconductors,
Phys. Rev. B 86, 085135 (2012)

A. Dal Corso,
Projector augmented-wave method: application to relativistic
spin-density functional theory,
Phys. Rev. B 82, 075116 (2010).

Pseudopotentials with spin-orbit and other tests:
A. Dal Corso,
Pseudopotentials periodic table: from H to Pu,
Comp. Material Science 95, 337 (2014).

and you will find the references to this kind of calculation

If you want to know the meaning of the variables in the input files,  
then look here

your-path-to-QE/Doc/INPUT_PW.txt

HTH

Giuseppe

Quoting tanmay chaki :

> I am new in quantum espresso.pls help me how to calculate scf with  spin
> orbit coupling


-- 

- Article premier - Les hommes naissent et demeurent
libres et égaux en droits. Les distinctions sociales
ne peuvent être fondées que sur l'utilité commune
- Article 2 - Le but de toute association politique
est la conservation des droits naturels et
imprescriptibles de l'homme. Ces droits sont la liberté,
la propriété, la sûreté et la résistance à 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/en/staff/giuseppe-mattioli/
ResearcherID: F-6308-2012


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[Pw_forum] Spin orbit coupling

[tanmay chaki]

I am new in quantum espresso.pls help me how to calculate scf with  spin
orbit coupling
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Re: [Pw_forum] Spin orbit coupling in MoS2/WS2 systems

[Krishnamohan]

Dear Kanak,

You can find Fully relativistic pseudopotentials in PSL. Please see the
folowing Link.

http://theossrv1.epfl.ch/Main/Pseudopotentials

Please test them yourself before using.

On Wed, May 4, 2016 at 10:51 AM, Kanak Datta  wrote:

> Dear researchers
>
> For spin orbit coupling inclusion in bandstructure calculation, we need to
> use fully relativistic pseudopotentials as suggested here:
>
> http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide/node10.html
>
> I wand to study the electronic properties of MoS2/WS2 bilayer system with
> spin orbit coupling. However, I could not find any fully relativistic
> pseudopotential in the library:
>
> http://www.quantum-espresso.org/pseudo-search-results/?el_id=74&unp_id&fun_id&colum_k&origin_id
>
> So, for DFT calculation of MoS2/WS2 bilayers with spin orbit correction,
> what should be done? I have already done the calculation w/o spin orbit
> coupling.
>
> Thanks in advance.
>
> Sincerely yours
> Kanak
> EEE, BUET
>
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-- 
*Krishnamohan Thekkepat*
*Research Associate*
*Indo-Korea Science and Technology Center, Bangalore, India*

“We shall not cease from exploration, and the end of all our exploring will
be to arrive where we started and know the place for the first time.”- T.S
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[Pw_forum] Spin orbit coupling in MoS2/WS2 systems

[Kanak Datta]

Dear researchers

For spin orbit coupling inclusion in bandstructure calculation, we need to
use fully relativistic pseudopotentials as suggested here:
http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide/node10.html

I wand to study the electronic properties of MoS2/WS2 bilayer system with
spin orbit coupling. However, I could not find any fully relativistic
pseudopotential in the library:
http://www.quantum-espresso.org/pseudo-search-results/?el_id=74&unp_id&fun_id&colum_k&origin_id

So, for DFT calculation of MoS2/WS2 bilayers with spin orbit correction,
what should be done? I have already done the calculation w/o spin orbit
coupling.

Thanks in advance.

Sincerely yours
Kanak
EEE, BUET
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[Pw_forum] spin-orbit coupling in LDA+U calculations

[Ram Krishna Ghosh]

Dear QE users,
I am curious whether can we use non collinear spin-orbit coupling in LDA+U
calculations? Any suggestion !

Thanks
Ram
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Re: [Pw_forum] Spin-Polarized NEB

[Mostafa Youssef]

Thank you very much, Giuseppe !


Best Regards,
Mostafa
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Re: [Pw_forum] Spin-Polarized NEB

[Giuseppe Mattioli]

Dear Mostafa
I'm abroad and have no access to my publications archive.
However, a brief but interesting quantum chemical account can be found  
in the ORCA (a quantum chemistry suite of codes) manual at pages  
49-51. The pdf manual can be found here:
http://www.cec.mpg.de/media/Forschung/ORCA/orca_manual_3_0_1.pdf

Best Wishes
Giuseppe

Quoting Mostafa Youssef :

> Dear Giuseppe,
>
>
> The ethylene rotation example you mentioned is very interesting.  I  
> wonder if there is a reference you recommend that carefully analyzed  
> this case with DFT or other quantum chemical approaches.
>
>
> Best Regards,
> Mostafa
> MIT


-- 

- Article premier - Les hommes naissent et demeurent
libres et égaux en droits. Les distinctions sociales
ne peuvent être fondées que sur l'utilité commune
- Article 2 - Le but de toute association politique
est la conservation des droits naturels et
imprescriptibles de l'homme. Ces droits sont la liberté,
la propriété, la sûreté et la résistance à 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/en/staff/giuseppe-mattioli/
ResearcherID: F-6308-2012


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Re: [Pw_forum] Spin-Polarized NEB

[Mostafa Youssef]

Dear Giuseppe,


The ethylene rotation example you mentioned is very interesting.  I wonder if 
there is a reference you recommend that carefully analyzed this case with DFT 
or other quantum chemical approaches.


Best Regards,
Mostafa
MIT



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Re: [Pw_forum] Spin-Polarized NEB

[Giuseppe Mattioli]

Dear Victor
I see two levels at which your question can be answered.
At a technical level, the pw.x code (the "engine" of neb.x) starts from scratch 
the scf cycle of every image. If all your images converge the first scf 
iteration to a non-magnetic state then a) they will propagate the non-magnetic 
state to the following neb steps and b) the transition state might 
really be non-magnetic. You can force a paramagnetic ground state 
(tot_magnetization =/ 0) to have a paramagnetic transition state. However, note 
that 
at a "quantum chemistry" level, if you are right then your system jumps 
somewhere between a 2S+1=1 to a 2S+1=3 state (and then revert to a 2S+1=1 
state in the end? Sounds strange but not unheard of, e.g. the rotation of 
ethylene around the double bond), and this cannot be mapped along a single 
PES. You could calculate the fully diamagnetic and fully paramamagnetic paths 
(i.e., including initial and final configurations, by constraining the 
tot_magnetization value) and then see if the paramagnetic curve goes below the 
diamagnetic curve around the transition state. Be aware of the fact 
that if your transition state is intrinsically a multireference state (e.g., a 
diradical like twisted ethylene, which cannot be described by a single 
determinant), then DFT-based numbers could be poor numbers...
HTH
Giuseppe

On Monday, February 08, 2016 06:26:29 AM Vic Bermudez wrote:
> Hello,
> 
>   I'm doing a NEB calculation for a reaction where I suspect that the
> transition state might be paramagnetic. In the "engine_input" section I set
> 'nspin=2', and I set a non-zero starting magnetization for one of the atom
> types. In the first SCF cycle of the first NEB iteration the absolute
> magnetization is initially non-zero and converges to a zero absolute
> magnetization. The total magnetization remains zero at all times. This
> applies to all 15 of the NEB images.
>   However, in successive NEB iterations the SCF starts right from the
> beginning with zero absolute and total magnetizations and remains at zero
> for both quantities right up to SCF convergence.
>   Here's my question. Given all this, am I really doing a spin-polarized
> calculation, or is my calculation actually spin-restricted. If the latter,
> what should I be doing to get a spin-unrestricted NEB run ?
> 
> Thank you in advance for your help.
> 
> This is the relevant part of the input. Here I'm restarting a calculation
> that was spin-restricted and appeared to be getting somewhat close to NEB
> convergence
> 
> BEGIN
> BEGIN_PATH_INPUT
> &PATH
> restart_mode='restart',
> string_method='neb',
> ds=1.D0,
> opt_scheme='broyden',
> nstep_path=4000,
> num_of_images=15,
> k_max=0.6D0,
> k_min=0.1D0,
> first_last_opt=.TRUE.,
> use_freezing=.TRUE.,
> CI_scheme='auto'
> /
> END_PATH_INPUT
> 
> BEGIN_ENGINE_INPUT
> &CONTROL
> title='NEB Run',
> ! restart_mode='from_scratch',
> pseudo_dir='/lustre/cmf/scratch/b/bermudez/QE_PP/',
> ! outdir='/lustre/cmf/scratch/b/bermudez/NEB-SO2_2/',
> etot_conv_thr=1.0D-4,
> forc_conv_thr=1.0D-3,
> verbosity='default'
> /
> 
> &SYSTEM
> ibrav=8,
> a=14.5898, b=14.7815, c=35.00,
> nat=138,
> ntyp=4,
> ecutwfc=40.0,
> ecutrho=400.0,
> nspin=2,
> starting_magnetization(1)=0.0,
> starting_magnetization(2)=0.0,
> starting_magnetization(3)=0.0,
> starting_magnetization(4)=0.,
> london=.true.,
> occupations='smearing',
> smearing='gaussian',
> degauss=0.002,
> nosym=.TRUE.
> /
> 
> &ELECTRONS
> electron_maxstep=200,
> conv_thr=3.0D-9,
> mixing_beta=0.7D0,
> mixing_ndim=8,
> mixing_mode='local-TF'
> /
> 
> ATOMIC_SPECIES
> Zr 91.22   Zr.pbe-spn-kjpaw_psl.0.2.3.UPF
> O  15.9994  O.pbe-n-kjpaw_psl.0.1.UPF
> H   1.0079  H.pbe-kjpaw_psl.0.1.UPF
> S  32.06S.pbe-n-kjpaw_psl.0.1.UPF
> 
> 
> Victor M. Bermudez
> E-mail: bermu...@alum.mit.edu
> 
> 
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- Article premier - Les hommes naissent et demeurent
libres et égaux en droits. Les distinctions sociales
ne peuvent être fondées que sur l'utilité commune
- Article 2 - Le but de toute association politique
est la conservation des droits naturels et 
imprescriptibles de l'homme. Ces droits sont la liberté,
la propriété, la sûreté et la résistance à l'oppression.


   Giuseppe Mattioli
   CNR - ISTITUTO DI STRUTTURA DELLA MATERIA   
   v. Salaria Km 29,300 - C.P. 10
   I 00015 - Monterotondo Stazione (RM), Italy
   Tel + 39 06 90672836 - Fax +39 06 90672316
   E-mail: 
   http://www.ism.cnr.it/english/staff/mattiolig
   ResearcherID: F-6308-2012

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[Pw_forum] Spin-Polarized NEB

[Vic Bermudez]

Hello,

I'm doing a NEB calculation for a reaction where I suspect that the
transition state might be paramagnetic. In the "engine_input" section I set
'nspin=2', and I set a non-zero starting magnetization for one of the atom
types. In the first SCF cycle of the first NEB iteration the absolute
magnetization is initially non-zero and converges to a zero absolute
magnetization. The total magnetization remains zero at all times. This
applies to all 15 of the NEB images.
However, in successive NEB iterations the SCF starts right from the
beginning with zero absolute and total magnetizations and remains at zero
for both quantities right up to SCF convergence.
Here's my question. Given all this, am I really doing a spin-polarized
calculation, or is my calculation actually spin-restricted. If the latter,
what should I be doing to get a spin-unrestricted NEB run ?

Thank you in advance for your help.

This is the relevant part of the input. Here I'm restarting a calculation
that was spin-restricted and appeared to be getting somewhat close to NEB
convergence

BEGIN
BEGIN_PATH_INPUT
&PATH
restart_mode='restart',
string_method='neb',
ds=1.D0,
opt_scheme='broyden',
nstep_path=4000,
num_of_images=15,
k_max=0.6D0,
k_min=0.1D0,
first_last_opt=.TRUE.,
use_freezing=.TRUE.,
CI_scheme='auto'
/
END_PATH_INPUT

BEGIN_ENGINE_INPUT
&CONTROL
title='NEB Run',
! restart_mode='from_scratch',
pseudo_dir='/lustre/cmf/scratch/b/bermudez/QE_PP/',
! outdir='/lustre/cmf/scratch/b/bermudez/NEB-SO2_2/',
etot_conv_thr=1.0D-4,
forc_conv_thr=1.0D-3,
verbosity='default'
/

&SYSTEM
ibrav=8,
a=14.5898, b=14.7815, c=35.00,
nat=138,
ntyp=4,
ecutwfc=40.0,
ecutrho=400.0,
nspin=2,
starting_magnetization(1)=0.0,
starting_magnetization(2)=0.0,
starting_magnetization(3)=0.0,
starting_magnetization(4)=0.,
london=.true.,
occupations='smearing',
smearing='gaussian',
degauss=0.002,
nosym=.TRUE.
/

&ELECTRONS
electron_maxstep=200,
conv_thr=3.0D-9,
mixing_beta=0.7D0,
mixing_ndim=8,
mixing_mode='local-TF'
/

ATOMIC_SPECIES
Zr 91.22   Zr.pbe-spn-kjpaw_psl.0.2.3.UPF
O  15.9994  O.pbe-n-kjpaw_psl.0.1.UPF
H   1.0079  H.pbe-kjpaw_psl.0.1.UPF
S  32.06S.pbe-n-kjpaw_psl.0.1.UPF


Victor M. Bermudez
E-mail: bermu...@alum.mit.edu


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Re: [Pw_forum] Spin orbit coupling with hybrid functional

[Prasenjit Ghosh]

Thanks Lorenzo.

Prasenjit

On 5 December 2015 at 01:08, Lorenzo Paulatto <
lorenzo.paula...@impmc.upmc.fr> wrote:

> On Friday, December 04, 2015 05:44:59 PM Prasenjit Ghosh wrote:
> > Dear all,
> >
> > Is it possible to do spin-orbit calculations with hybrid functionals in
> QE?
> >
> > With regards,
> >
> > Prasenjit
>
> Yes, but only norm-conserving pseudpotentials
>
> --
> 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
>
>
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-- 
PRASENJIT GHOSH,
IISER Pune,
Dr. Homi Bhabha Road, Pashan
Pune, Maharashtra 411008, India

Phone: +91 (20) 2590 8203
Fax: +91 (20) 2589 9790
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Re: [Pw_forum] Spin orbit coupling with hybrid functional

[Lorenzo Paulatto]

On Friday, December 04, 2015 05:44:59 PM Prasenjit Ghosh wrote:
> Dear all,
> 
> Is it possible to do spin-orbit calculations with hybrid functionals in QE?
> 
> With regards,
> 
> Prasenjit

Yes, but only norm-conserving pseudpotentials

-- 
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


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[Pw_forum] Spin orbit coupling with hybrid functional

[Prasenjit Ghosh]

Dear all,

Is it possible to do spin-orbit calculations with hybrid functionals in QE?

With regards,

Prasenjit

-- 
PRASENJIT GHOSH,
IISER Pune,
Dr. Homi Bhabha Road, Pashan
Pune, Maharashtra 411008, India

Phone: +91 (20) 2590 8203
Fax: +91 (20) 2589 9790
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Re: [Pw_forum] Spin-Orbit Calculation

[Ajit Kumar Jena]

Thanks a lot Roberta for your informative reply.

___
Ajit
On 10-Sep-2015 10:30 pm, "roberta pigliapochi" 
wrote:

> Dear Ajit,
> please bear in mind that I AM NOT AN EXPERT and I would instead really
> appreciate comments from more experienced users. I will try to give some
> advice but take it with a pinch of salt. I would also like to follow up on
> this by asking:
>
> can noncolinear calculations and DFT+U go together now?
>
> Referring to your points:
>
> 1)the AFM initial guess is set up fine. The system might still converge to
> a FM situation, though. If instead you'd rather force it to stay AFM I'd go
> for 'tot_magnetization'
> 2)yes. You may also need to specify lda_plus_u=.true. beforehand.
> 3)I'd say so, and I also think that the 'angle' isn't a fixed value but
> rather will be optimised during the scf. Instead if you'd prefer the two
> (or total) magnetizations to be kept fixed along y I'd go for
> 'constrained_magnetization'
> 4)I think that the default 'domag' (whatever it means) is set to false,
> hence there should be no need for your flag to be there. Also, 'nspin=4'
> may be redundant considering that you have set 'noncolin=.true.'
>
> hope some more hard-core expert will comment on this.
>
> good luck (:
> Roberta
>
> Roberta Pigliapochi
> PhD Student | Grey Research Group
> University of Cambridge
>
>
> On 8 September 2015 at 12:48, Ajit Kumar Jena  wrote:
>
>> Dear All,
>> I wish to do a *spin-orbit calculation* of our system
>> (LiFePO4) which involves iron (Fe) as a magnetic element. Her*e *I am
>> providing my input variables containing the system name lists and atomic
>> species.
>>
>> My questions are the following :
>>
>> 1) As it is mentioned in the input, should I consider two different types
>> of spins ( up and down ) to do a anti-ferromagnetic calculation ?
>> 2) The way I have incorporated Hubbard 'U' is appropriate or not ?
>> 3) If I am giving the inputs in this way, will it take the starting spin
>> quantization axis along Y-direction or not ?
>> 4) Is there any problem if i will not include " starting_spin_angle =
>> .true. " ?
>>
>> Any kind of help is highly appreciated. I am extremely sorry if my
>> questions are very trivial.
>>
>> *Input*
>> &system
>> ibrav=  8,
>> celldm(1) = 19.326236,
>> celldm(2) = 0.587151,
>> celldm(3) = 0.458766,
>> nat=  28,
>> ntyp= 7,
>> !nspin = 4,
>> starting_magnetization(2) = 0.7,
>> starting_magnetization(3) = -0.7,
>> ecutwfc =30.0,
>> ecutrho = 250.0,
>> occupations = 'smearing' ,
>> degauss = 0.001 ,
>> smearing = 'gaussian' ,
>> noncolin = .true.
>> lspinorb = .true.
>> starting_spin_angle = .true.
>> angle1(2) = 90.0
>> angle2(2) = 90.0
>> angle1(3) = 90.0
>> angle2(3) = 90.0
>> lda_plus_u_kind = 0,
>> Hubbard_U(2)=3.0,
>> Hubbard_U(3)=3.0,
>>
>> ATOMIC_SPECIES
>>  Li1  6.94  Li.pbe-s-van_ak.UPF
>>  Fe1  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
>>  Fe2  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
>>  P1   30.9737   P.pbe-van_ak.UPF
>>  O1   15.999O.pbe-van_ak.UPF
>>  O2   15.999O.pbe-van_ak.UPF
>>  O3   15.999O.pbe-van_ak.UPF
>>
>> Thanks & Regards,
>> Ajit,
>> IIT Madras, Chennai
>>
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>
>
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Re: [Pw_forum] Spin-Orbit Calculation

[roberta pigliapochi]

Dear Ajit,
please bear in mind that I AM NOT AN EXPERT and I would instead really
appreciate comments from more experienced users. I will try to give some
advice but take it with a pinch of salt. I would also like to follow up on
this by asking:

can noncolinear calculations and DFT+U go together now?

Referring to your points:

1)the AFM initial guess is set up fine. The system might still converge to
a FM situation, though. If instead you'd rather force it to stay AFM I'd go
for 'tot_magnetization'
2)yes. You may also need to specify lda_plus_u=.true. beforehand.
3)I'd say so, and I also think that the 'angle' isn't a fixed value but
rather will be optimised during the scf. Instead if you'd prefer the two
(or total) magnetizations to be kept fixed along y I'd go for
'constrained_magnetization'
4)I think that the default 'domag' (whatever it means) is set to false,
hence there should be no need for your flag to be there. Also, 'nspin=4'
may be redundant considering that you have set 'noncolin=.true.'

hope some more hard-core expert will comment on this.

good luck (:
Roberta

Roberta Pigliapochi
PhD Student | Grey Research Group
University of Cambridge


On 8 September 2015 at 12:48, Ajit Kumar Jena  wrote:

> Dear All,
> I wish to do a *spin-orbit calculation* of our system
> (LiFePO4) which involves iron (Fe) as a magnetic element. Her*e *I am
> providing my input variables containing the system name lists and atomic
> species.
>
> My questions are the following :
>
> 1) As it is mentioned in the input, should I consider two different types
> of spins ( up and down ) to do a anti-ferromagnetic calculation ?
> 2) The way I have incorporated Hubbard 'U' is appropriate or not ?
> 3) If I am giving the inputs in this way, will it take the starting spin
> quantization axis along Y-direction or not ?
> 4) Is there any problem if i will not include " starting_spin_angle =
> .true. " ?
>
> Any kind of help is highly appreciated. I am extremely sorry if my
> questions are very trivial.
>
> *Input*
> &system
> ibrav=  8,
> celldm(1) = 19.326236,
> celldm(2) = 0.587151,
> celldm(3) = 0.458766,
> nat=  28,
> ntyp= 7,
> !nspin = 4,
> starting_magnetization(2) = 0.7,
> starting_magnetization(3) = -0.7,
> ecutwfc =30.0,
> ecutrho = 250.0,
> occupations = 'smearing' ,
> degauss = 0.001 ,
> smearing = 'gaussian' ,
> noncolin = .true.
> lspinorb = .true.
> starting_spin_angle = .true.
> angle1(2) = 90.0
> angle2(2) = 90.0
> angle1(3) = 90.0
> angle2(3) = 90.0
> lda_plus_u_kind = 0,
> Hubbard_U(2)=3.0,
> Hubbard_U(3)=3.0,
>
> ATOMIC_SPECIES
>  Li1  6.94  Li.pbe-s-van_ak.UPF
>  Fe1  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
>  Fe2  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
>  P1   30.9737   P.pbe-van_ak.UPF
>  O1   15.999O.pbe-van_ak.UPF
>  O2   15.999O.pbe-van_ak.UPF
>  O3   15.999O.pbe-van_ak.UPF
>
> Thanks & Regards,
> Ajit,
> IIT Madras, Chennai
>
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[Pw_forum] Spin-Orbit Calculation

[Ajit Kumar Jena]

Dear All,
I wish to do a *spin-orbit calculation* of our system (LiFePO4)
which involves iron (Fe) as a magnetic element. Her*e *I am providing my
input variables containing the system name lists and atomic species.

My questions are the following :

1) As it is mentioned in the input, should I consider two different types
of spins ( up and down ) to do a anti-ferromagnetic calculation ?
2) The way I have incorporated Hubbard 'U' is appropriate or not ?
3) If I am giving the inputs in this way, will it take the starting spin
quantization axis along Y-direction or not ?
4) Is there any problem if i will not include " starting_spin_angle =
.true. " ?

Any kind of help is highly appreciated. I am extremely sorry if my
questions are very trivial.

*Input*
&system
ibrav=  8,
celldm(1) = 19.326236,
celldm(2) = 0.587151,
celldm(3) = 0.458766,
nat=  28,
ntyp= 7,
!nspin = 4,
starting_magnetization(2) = 0.7,
starting_magnetization(3) = -0.7,
ecutwfc =30.0,
ecutrho = 250.0,
occupations = 'smearing' ,
degauss = 0.001 ,
smearing = 'gaussian' ,
noncolin = .true.
lspinorb = .true.
starting_spin_angle = .true.
angle1(2) = 90.0
angle2(2) = 90.0
angle1(3) = 90.0
angle2(3) = 90.0
lda_plus_u_kind = 0,
Hubbard_U(2)=3.0,
Hubbard_U(3)=3.0,

ATOMIC_SPECIES
 Li1  6.94  Li.pbe-s-van_ak.UPF
 Fe1  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
 Fe2  55.845Fe.rel-pbe-spn-rrkjus_psl.0.2.1.UPF
 P1   30.9737   P.pbe-van_ak.UPF
 O1   15.999O.pbe-van_ak.UPF
 O2   15.999O.pbe-van_ak.UPF
 O3   15.999O.pbe-van_ak.UPF

Thanks & Regards,
Ajit,
IIT Madras, Chennai
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[Pw_forum] Spin orbit projwfc error

[Rajdeep Banerjee]

Dear all,
I was trying to run projected density of states from an nscf
calculation with spin-orbit included and I am getting the following error:


 Calling projwave_nc 

 %%
 Error in routine d_matrix_so (5):
 D_S (j=1/2) for this symmetry operation is not unitary
 %%

 stopping ...

I am running it on espresso-5.0.1 and I am attaching the scf,
nscf and pdos inputs so that one can reproduce the error.
Please help me if anyone has any idea on how to resolve the
issue.
(as far as I know the previous discussions on this issue in pw_forum
doesn't reach any conclusive result. So I am asking again. Very sorry for
repitition)

Thanks amd regards,
-- 
Rajdeep Banerjee
PhD student
JNCASR, Bangalore
India


alat-8.64570_strain-0.05_scf.in
Description: Binary data


alat-8.64570_strain-0.05_pdos.out
Description: Binary data


alat-8.64570_strain-0.05_pdos.in
Description: Binary data


alat-8.64570_strain-0.05_nscf.in
Description: Binary data
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[Pw_forum] spin-orbit coupling

[Shoutao Zhang]

Dear all,
I would like to know how to take into consideration the spin-orbit coupling 
(SOC) when calculating the superconducting transition temperature by means of 
the Quantum ESPRESSO package. May you send  the relative input files to me ? 

 Thanks for your help and I look forward to hearing from you soon.





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Re: [Pw_forum] spin polarization

[Mostafa Youssef]

Hi Tayebeh

I think all what you need to calculate a helix of magntic moments for Co ions 
in  SrCO3 would be:

1- Noncollinear calculations.
2- A larger supercell to accommodate the helix.
3- Fully relativistic pseudopotentials (such as those in Pslib)
4- Define different Co species each with different direction for the magnetic 
moment
5- You might also wish to use vc_relax rather than relax with cell_dofree to 
fix the volume but vary the shape of the cell. Or just vc_relax if you want to 
get a quick answer.


I think all these ingredients are available and Pwscf is ready to tackle SrCO3 !


Mostafa Youssef
MIT

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[Pw_forum] spin polarization

[Tayebeh Roohande]

Dear Quantum-ESPRESSO users and developers,

I want to optimize lattice parameter of my structure(SrCoO3). I calculated
(relaxation)  . The lattice parameter was varied in steps of 0.005 angstrom
.For magnetization of cobalt  ,I used "start magnetization"  for Co  . but
in others papers lattice parameter of SrCO3 is reported by  Co ion
multiplicity(spin state of cobalt)!! for example for Co ion multiplicity 4
,lattice parameter is 3.90 and for Co ion multiplicity 6, lattice parameter
is 3.954!!
How Co ion multiplicity in input of  relax calculation(PW.X) is effected?
here i attached input file of relax(for optimization of  lattice parameter)


Sincerely
Tayebeh Roohandeh
modares university-IRAN


sco.in
Description: Binary data
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Re: [Pw_forum] spin-polarized band structure plots for SO coupling (nicvok)

[Rajdeep Banerjee]

Dear Nicki Frank Hinsche,
  thank you very much for your kind
help.

thanks and regards,
Rajdeep Banerjee
Rajdeep Banerjee
PhD student
Theoretical Sciences Unit
JNCASR, Bangalore
India
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[Pw_forum] spin-polarized band structure plots for SO coupling

[nicvok]

In the case of spin-orbit coupling there is no proper spin up/ down  
anymore - one should keep this in mind! You need to project the spin  
expectation value on a

chosen quantization axis -> QE can do this 
http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_BANDS.html

best regards Nicki

-
Nicki Frank Hinsche, Dr. rer. nat.
Institute of physics - Theoretical physics,
Martin-Luther-University Halle-Wittenberg,
Von-Seckendorff-Platz 1, Room 1.07
D-06120 Halle/Saale, Germany
Tel.: ++49 345 5525460
-



Dear all,
   how can I plot spin-polarized band structure (for spin up  
and
spin down bands separately) for a calculation with spin orbit  
coupling?



Thanks in advance.


thanks and regards,
Rajdeep Banerjee
PhD student
Theoretical Sciences Unit
JNCASR, Bangalore
India





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[Pw_forum] spin-polarized band structure plots for SO coupling

[Rajdeep Banerjee]

Dear all,
how can I plot spin-polarized band structure (for spin up and
spin down bands separately) for a calculation with spin orbit coupling?


Thanks in advance.


thanks and regards,
Rajdeep Banerjee
PhD student
Theoretical Sciences Unit
JNCASR, Bangalore
India
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[Pw_forum] Spin-orbit + electron-phonon?

[Paolo Giannozzi]

On Fri, 2014-08-01 at 15:34 +, Ij?s Mari wrote:

> I tried searching the forum, as well as looking at the beginning of ph.f90 
> file. 

there is no ph.f90 file. There is a phonon.f90 file, containing in 
the header the following lines:

  ! ... Presently implemented:
  ! ... dynamical matrix (q/=0)   NC [4], US [4], PAW [4]
  ! ... dynamical matrix (q=0)NC [5], US [5], PAW [4]
  ! ... dielectric constant   NC [5], US [5], PAW [3]
  ! ... born effective chargesNC [5], US [5], PAW [3]
  ! ... polarizability (iu)   NC [2], US [2]
  ! ... electron-phonon   NC [3], US [3]
  ! ... electro-optic NC [1]
  ! ... raman tensor  NC [1]
  !
  ! NC = norm conserving pseudopotentials
  ! US = ultrasoft pseudopotentials
  ! PAW = projector augmented-wave
  ! [1] LDA,
  ! [2] [1] + GGA,
  ! [3] [2] + LSDA/sGGA,
  ! [4] [3] + Spin-orbit/nonmagnetic,
  ! [5] [4] + Spin-orbit/magnetic (experimental when available)
  !

> Is performing electron-phonon coupling calculations in a system with 
> spin-orbit coupling possible?

no - P.

-- 
Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222 

[Pw_forum] Spin-orbit + electron-phonon?

[Ijäs Mari]

Dear forum members, 

I?m sorry, if this has been asked before - I tried searching the forum, as well 
as looking at the beginning of ph.f90 file. 

Is performing electron-phonon coupling calculations in a system with spin-orbit 
coupling possible?

Best, 

Mari  


Dr. Mari Ij?s
Room 114, CAPE
Cambridge Graphene Centre
9 JJ Thomson Avenue
CB3 0FA, Cambridge, UK
+441223748349

[Pw_forum] spin orbit coupling

[Samin, Adib J.]

Dear Quantum Espresso users,


I would like to carry out a calculation where I include spin-orbit coupling for 
Neodymium to examine its magnetic properties. It is my understanding that fully 
relativistic pseudopotentials are needed for such a calculation.

Unfortunately, I have not been able to find any relativistic pseudopotentials 
for the two atoms I am interested in (Nd, and Sm).

I am uncertain how to proceed because I know that the RS coupling scheme is 
commonly used for these atoms and I would expect the orbital contribution to be 
important for the calculation.

Finally, can spin-orbit coupling be used with LSDA? I ask this question because 
carrying out a spin-orbit calculation in Qunatum Espresso requires specifying 
noncolin=.true.


I would greatly appreciate any clarifications on this issue.


Thanks,

Adib Samin


Adib Samin

Graduate Fellow

The Department of Aerospace and Mechanical Engineering

The Ohio State University


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[Pw_forum] Spin Calculations.

[Nguyen Chuong]

Hi Everyone.

As I know, Quantum Espresso can do spin-polarized (nspin = 2 in script) and
spin-unpolarized (nspin =1) calculations. But I have a question, that same
its mean with spin-unrestricted and spin-restricted wavefunctions?

Thanks.

-- 
Nguyen Van Chuong
PhD Student,
Department of Physics,
Don State Technical University.
Rostov on Don, Russia
Group Graphene
Email: chuongnguyen11 at gmail.com or cpuphys86 at gmail.com
Website: http://cpuphys86.webs.com/
Phone mobile: +7 905 45 94 888
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[Pw_forum] Spin polarized surface band

[Peng Chen]

Dear Professor Burton,

Thank you very much for the reply. Does that mean surface band should be
doubly degenerate, whereas bulk bands are quadruply degnerate, otherwise
how do we identify the surface state? In my calculated results, almost all
bands are just doubly degenerate.

And from literature, the sign of spin moment in Gamma-M  direction is
opposite to that in Gmma-K  direction, whereas, there is no any trend in my
result.I also checked sigma(y) and sigma(z) component, there is also no
trend.


On Thu, Feb 20, 2014 at 10:56 AM, J. D. Burton  wrote:

> Hi Peng,
>
>
>
> Each band is doubly-degenerate because your slab has two surfaces: A
> spin-polarized pair of bands for the top surface, and an
> oppositely-spin-polarized pair of bands for the bottom surface.
>
>
>
> Cheers,
>
> J. D.
>
>
>
>
>
> 
>
> J. D. Burton, Ph.D.
>
> jdburton1 at gmail.com
>
> Research Assistant Professor
>
> University of Nebraska Lincoln
>
> Physics and Astronomy
>
> Office Ph. (402) 472 2499
>
> Mobile Ph. (402) 419 9918
>
> 310A Jorgensen Hall
>
> CV: http://tinyurl.com/2avltsc
>
> 
>
> "The job of a scientist is to generate wrong ideas as fast as possible."
>
> -- Murray Gell-Mann
>
>
>
> *From:* pw_forum-bounces at pwscf.org [mailto:pw_forum-bounces at pwscf.org] 
> *On
> Behalf Of *Peng Chen
> *Sent:* Monday, February 17, 2014 8:11 PM
> *To:* PWSCF Forum
> *Subject:* [Pw_forum] Spin polarized surface band
>
>
>
> Hello Everyone,
>
>
>
> Bi2Se3 slab with 6 quintuple layers is calculated. It is supposed to have
> spin polarized non-degenerate surface bands. However, in the calculated
> results, each band is doubly degenerated including surface band, as shown
> in the left panel of attached figure. And the spin components (sigma x)
> have opposite sign for degenerated surface band (S1). The input is listed
> below. I am not sure if I am doing the right thing. Any suggestions are
> welcome!
>
>
>
> &control
>
> calculation='scf'
>
> wf_collect=.TRUE.
>
> restart_mode='from_scratch',
>
> prefix='BiSe.6QL.pbe.spin',
>
> pseudo_dir = '/data/espresso-5.0/pseudo/',
>
> outdir='/data/scratch/'
>
>  /
>
>  &system
>
> ibrav=4, celldm(1)=7.8196867, celldm(3)=17
>
>  nat=30, ntyp=2,
>
>  noncolin=.TRUE, lspinorb=.TRUE.
>
>   starting_magnetization(1)=-0.1,
>
>  ecutwfc = 60, ecutrho = 600,nbnd=360
>
>   occupations='smearing', smearing='mv', degauss=0.015
>
>  /
>
>
>
>  &electrons
>
> conv_thr = 1.0e-7
>
> mixing_mode='local-TF'
>
> mixing_beta = 0.7
>
>  /
>
>
>
> ATOMIC_SPECIES
>
>  Bi 208.98040 Bi.rel-pbe-dn-rrkjus_psl.1.0.0.UPF
>
>  Se  78.96  Se.rel-pbe-n-rrkjus_psl.1.0.0.UPF
>
>
>
> ATOMIC_POSITIONS angstrom
>
> Se 0 0 5.899840007
>
> ..
>
> Se 2.069 1.194537707 60.92682666
>
> K_POINTS (automatic)
>
>  10 10 1 0 0 0
>
>
>
>
>
> --
>   Best Regards.
> Peng
>
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-- 
  Best Regards.
Peng
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[Pw_forum] Spin polarized surface band

[J. D. Burton]

Hi Peng,

 

Each band is doubly-degenerate because your slab has two surfaces: A
spin-polarized pair of bands for the top surface, and an
oppositely-spin-polarized pair of bands for the bottom surface.

 

Cheers,

J. D.

 

 



J. D. Burton, Ph.D.

 <mailto:jdburton1 at gmail.com> jdburton1 at gmail.com

Research Assistant Professor

University of Nebraska Lincoln

Physics and Astronomy

Office Ph. (402) 472 2499

Mobile Ph. (402) 419 9918

310A Jorgensen Hall

CV:  <http://tinyurl.com/2avltsc> http://tinyurl.com/2avltsc



"The job of a scientist is to generate wrong ideas as fast as possible."

-- Murray Gell-Mann

 

From: pw_forum-bounces at pwscf.org [mailto:pw_forum-boun...@pwscf.org] On
Behalf Of Peng Chen
Sent: Monday, February 17, 2014 8:11 PM
To: PWSCF Forum
Subject: [Pw_forum] Spin polarized surface band

 

Hello Everyone,

 

Bi2Se3 slab with 6 quintuple layers is calculated. It is supposed to have
spin polarized non-degenerate surface bands. However, in the calculated
results, each band is doubly degenerated including surface band, as shown in
the left panel of attached figure. And the spin components (sigma x) have
opposite sign for degenerated surface band (S1). The input is listed below.
I am not sure if I am doing the right thing. Any suggestions are welcome!

 

&control

calculation='scf'

wf_collect=.TRUE.

restart_mode='from_scratch',

prefix='BiSe.6QL.pbe.spin',

pseudo_dir = '/data/espresso-5.0/pseudo/',

outdir='/data/scratch/'

 /

 &system

ibrav=4, celldm(1)=7.8196867, celldm(3)=17

 nat=30, ntyp=2,

 noncolin=.TRUE, lspinorb=.TRUE.

  starting_magnetization(1)=-0.1,

 ecutwfc = 60, ecutrho = 600,nbnd=360

  occupations='smearing', smearing='mv', degauss=0.015

 /

 

 &electrons

conv_thr = 1.0e-7

mixing_mode='local-TF'

mixing_beta = 0.7

 /

 

ATOMIC_SPECIES

 Bi 208.98040 Bi.rel-pbe-dn-rrkjus_psl.1.0.0.UPF

 Se  78.96  Se.rel-pbe-n-rrkjus_psl.1.0.0.UPF

 

ATOMIC_POSITIONS angstrom

Se 0 0 5.899840007

.. 

Se 2.069 1.194537707 60.92682666

K_POINTS (automatic)

 10 10 1 0 0 0

 

 

-- 
  Best Regards.
Peng  

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[Pw_forum] Spin polarized surface band

[Peng Chen]

Hello Everyone,

Bi2Se3 slab with 6 quintuple layers is calculated. It is supposed to have
spin polarized non-degenerate surface bands. However, in the calculated
results, each band is doubly degenerated including surface band, as shown
in the left panel of attached figure. And the spin components (sigma x)
have opposite sign for degenerated surface band (S1). The input is listed
below. I am not sure if I am doing the right thing. Any suggestions are
welcome!

&control
calculation='scf'
wf_collect=.TRUE.
restart_mode='from_scratch',
prefix='BiSe.6QL.pbe.spin',
pseudo_dir = '/data/espresso-5.0/pseudo/',
outdir='/data/scratch/'
 /
 &system
ibrav=4, celldm(1)=7.8196867, celldm(3)=17
 nat=30, ntyp=2,
 noncolin=.TRUE, lspinorb=.TRUE.
  starting_magnetization(1)=-0.1,
 ecutwfc = 60, ecutrho = 600,nbnd=360
  occupations='smearing', smearing='mv', degauss=0.015
 /

 &electrons
conv_thr = 1.0e-7
mixing_mode='local-TF'
mixing_beta = 0.7
 /

ATOMIC_SPECIES
 Bi 208.98040 Bi.rel-pbe-dn-rrkjus_psl.1.0.0.UPF
 Se  78.96  Se.rel-pbe-n-rrkjus_psl.1.0.0.UPF

ATOMIC_POSITIONS angstrom
Se 0 0 5.899840007
..
Se 2.069 1.194537707 60.92682666
K_POINTS (automatic)
 10 10 1 0 0 0


-- 
  Best Regards.
Peng
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[Pw_forum] SPIN POLARIZATION CALCULATIONS

[xirainbow]

Dear Jamil,

> For a spin polarization calculations, for a molecular system,is that we must 
> take into account all the atoms considered in our system with 
> starting_magnetization or just take only one? In the second case, which atom 
> we must choose with starting_magnetization?

  It is up to you. If you do not know, no one else know the answer.
  In my experience in crystal calculations, the final
magnetization depends on the initial value. Starting with different
starting_magnetization, I can get para, ferro, or
antiferro-magnetization after scf calculations.

On Fri, Jan 24, 2014 at 5:49 PM, MISSAOUI Jamil
 wrote:
> Hi,
> I found problems with starting_magnetization, PLEASE, I want answers for
> these questions.
> 1 / For a spin polarization calculations, for a molecular system, is that we
> must take into account all the atoms considered in our system with
> starting_magnetization or just take only one? In the second case, which atom
> we must choose with starting_magnetization?
> 2 /Which value of starting_magnetization we fix  (between -1 and 1) in the
> case of spin polarization calculations, or we need a convergence
> calculations to fix it.?
> Thanks.
> Jamil.
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum



-- 

Hui Wang
School of physics, Henan University of Science and Technology, Henan, China

[Pw_forum] SPIN POLARIZATION CALCULATIONS

[MISSAOUI Jamil]

Hi, 
I found problems with starting_magnetization, PLEASE, I want answers for these 
questions. 
1 / For a spin polarization calculations, for a molecular system, is that we 
must take into account all the atoms considered in our system with 
starting_magnetization or just take only one? In the second case, which atom we 
must choose with starting_magnetization? 
2 /Which  value of starting_magnetization we fix?(between -1 and 1) in the case 
of spin polarization calculations, or we need a convergence calculations to fix 
it.?
Thanks. 
Jamil.
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[Pw_forum] spin polarization of a organo-metallic compound

[Giuseppe Mattioli]

Dear Alex
I note that the energy difference between spin-polarized and diamagnetic ground 
states in the B2PLYP calculations is much lower than in B3LYP, so my 
previous guess was not totally wrong. This is reassuring...:-) 
I can suggest some further checks on your last results before admitting (and it 
may still be possible... :-( ) that GTO and PW results are 
intrinsically incommensurable. I'm not familiar with Firefly, and I'm not sure 
if what I suggest can be actually done, so I apologize in advance...

a) If I understand and remember well you have performed your plane wave 
calculations with QE by using a "plain vanilla" PBE functional (no exx, no 
dft+u, no dispersion correction) Could you perform the same PBE calculation 
with Firefly? If the GTO results are similar to the PW ones the differences 
are not due to the basis sets but to the xc functionals.

b) I do not know your system, nor Firefly, so I cannot say for sure, but can 
you check if your GTO calculations include some dispersion correction 
(DFT-D3, usually) which may change the equilibrium geometry significantly wrt 
the PW case?

c) I see heavy elements in your molecule. Is there any trick which accounts for 
spin-orbit or relativistic contributions in your all-electron GTO 
calculations? If not, could you try to use some? I can suggest (if implemented) 
to try with effective core potentials (ECP. I've obtained good results 
with those contained here: 
http://www.theochem.uni-stuttgart.de/pseudopotentials/), which represent also 
the most similar setup to PW/pseudopotential 
calculations.

d) Did you push the ecutwfc/ecutrho limits further than 70/600 Ry in the PW 
calculations? I would suggest to reach at least 100/400 (yes, it is not a 
typo... 400 Ry on the electron density seem to be adequate for all of your US 
pseudopotentials, and NC pseudopotentials usually require a density 
cutoff not larger than 4*ecutwfc) and check the convergence of total energies.

e) There is no strict rule which forbids the use of US pseudopotentials 
together with NC ones, but if you pay the price (in terms of wfc cutoff) of the 
latter ones, you could try to use all NC... I've been comfortable since long 
with
O.pbe-mt.UPF
C.pbe-mt.UPF
H.pbe-vbc.UPF
which you should find in the online PP library.

HTH

Giuseppe


On Thursday 09 January 2014 07:11:56 Alex Granov wrote:
> Dear Giseppe
> Thank you very much for your kind attention and the details were said by
> you about spin polarization of such systems.I am sorry for the delay to
> reply your comments. I was doing what proposed by you and Stefano to see
> the difference origin. so in the following we can see the results
> obtained:
> Quantum -Espresso:
> ecutwfc = 70, ecutrho = 600,   (the cutoff has been increased as proposed
> by Stefano)Re 186.207  Re.pbe-mt_fhi.UPFO  15.999   O.pbe-rrkjus.UPFC
> 12.000C.pbe-rrkjus.UPFH 1.000 H.pbe-rrkjus.UPFI 126.90  
> I.pbe-mt_fhi.UPFP  30.9737  P.pbe-mt_fhi.UPF E=  -312.61421481 Ry
> (spin-unpolarized)E=  -312.66455244 Ry (spin-polarized, total
> magnetization=4.00 Bohr mag/cell
> 
> Firefly (Quantum Chemistry Code):
> B3LYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I  (the system optimized using this
> method) E (S=0) = -1202.07856 HartreeE (S=1) = -1202.06949 E (S=2) =
> -1202.04809 B2PLYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I (the energy of previous
> step was modified by adding the MP2 part as proposed by Giseppe) E (S=0) =
> -1199.826275 HartreeE (S=1) = -1199.825679 E (S=2) = -1199.820273
> 
> As still could be seen the plane-wave calculation shows that the
> spin-polarized system is the ground state and quantum chemistry
> calculation using Gaussian-like basis sets shows the trend conversely.
> 
> -Alex Granov??
> ??-???  (MIPT)Moscow, Russia



- 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: 
   ResearcherID: F-6308-2012
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[Pw_forum] spin polarization of a organo-metallic compound

[Alex Granov]

Dear Giseppe
Thank you very much for your kind attention and the details were said by you 
about spin polarization of such systems.I am sorry for the delay to reply your 
comments. I was doing what proposed by you and Stefano to see the difference 
origin.
so in the following we can see the results obtained:
Quantum -Espresso:
ecutwfc = 70, ecutrho = 600,   (the cutoff has been increased as proposed by 
Stefano)Re 186.207  Re.pbe-mt_fhi.UPFO  15.999   O.pbe-rrkjus.UPFC 12.000
C.pbe-rrkjus.UPFH 1.000 H.pbe-rrkjus.UPFI 126.90   I.pbe-mt_fhi.UPFP  
30.9737  P.pbe-mt_fhi.UPF
E=  -312.61421481 Ry (spin-unpolarized)E=  -312.66455244 Ry (spin-polarized, 
total magnetization=4.00 Bohr mag/cell

Firefly (Quantum Chemistry Code):
B3LYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I  (the system optimized using this method)
E (S=0) = -1202.07856 HartreeE (S=1) = -1202.06949 E (S=2) = -1202.04809
B2PLYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I (the energy of previous step was 
modified by adding the MP2 part as proposed by Giseppe)
E (S=0) = -1199.826275 HartreeE (S=1) = -1199.825679 E (S=2) = -1199.820273

As still could be seen the plane-wave calculation shows that the spin-polarized 
system is the ground state and quantum chemistry calculation using 
Gaussian-like basis sets shows the trend conversely. 

-Alex Granov?? 
??-???  (MIPT)Moscow, Russia
   
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[Pw_forum] spin polarization of a organo-metallic compound

[Jia Chen]

Dear Alex,

Thank you for your detailed information. I want to believe plane wave and
gaussian are both good for this type of calculations. And I would be
surprised if the difference really comes from functionals.

For you case, do you have reasons to believe Re pseudopotential is good? If
answers is no, maybe you can try different pseudopotentials for Re. Another
possibility I would consider is the cutoff. Pseudopoentails with d
electrons can be very hard. Sometimes, they need cutoff more than 100Ry. I
don't know the one you are using, but maybe it is a good idea to check. I
am not a big fan of mixing ultra-soft and norm-conserving pseudopotentials,
but maybe it is just my personal taste...

Cheers
Jia


On Thu, Jan 9, 2014 at 1:11 AM, Alex Granov  wrote:

> Dear Giseppe
>
> Thank you very much for your kind attention and the details were said by
> you about spin polarization of such systems.
> I am sorry for the delay to reply your comments. I was doing what proposed
> by you and Stefano to see the difference origin.
>
> so in the following we can see the results obtained:
>
> Quantum -Espresso:
>
> ecutwfc = 70, ecutrho = 600,   (the cutoff has been increased as proposed
> by Stefano)
> Re 186.207  Re.pbe-mt_fhi.UPF
> O  15.999   O.pbe-rrkjus.UPF
> C 12.000C.pbe-rrkjus.UPF
> H 1.000 H.pbe-rrkjus.UPF
> I 126.90   I.pbe-mt_fhi.UPF
> P  30.9737  P.pbe-mt_fhi.UPF
>
> E=  -312.61421481 Ry (spin-unpolarized)
> E=  -312.66455244 Ry (spin-polarized, total magnetization=4.00 Bohr
> mag/cell
>
>
> Firefly (Quantum Chemistry Code):
>
> B3LYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I  (the system optimized using this
> method)
>
> E (S=0) = -1202.07856 Hartree
> E (S=1) = -1202.06949
> E (S=2) = -1202.04809
>
> B2PLYP/6-31++G**:P,C,O,H; LANL2DZ:Re,I (the energy of previous step was
> modified by adding the MP2 part as proposed by Giseppe)
>
> E (S=0) = -1199.826275 Hartree
> E (S=1) = -1199.825679
> E (S=2) = -1199.820273
>
>
> As still could be seen the plane-wave calculation shows that the
> spin-polarized system is the ground state and quantum chemistry calculation
> using Gaussian-like basis sets shows the trend conversely.
>
>
> -
> Alex Granov
> ?? ??-???  (MIPT)
> Moscow, Russia
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 
Jia Chen
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[Pw_forum] spin polarization of a organo-metallic compound

[Giuseppe Mattioli]

Dear Jia
One last (at least for now...) word, which perhaps deserves to be  
written. Let us focus on excess electrons in transition metal oxides  
(only because I've studied them for long). If you create an O vacancy  
in Ti(IV)O2 the missing O atom lets back two excess electrons. If you  
perform a conventional DFT (i.e., PBE) calculation the two excess  
electrons are delocalized in the conduction band and the total  
magnetization is 0 muB. Here the delocalization (self interaction,  
double counting, ...) error spread "little pieces of electron" around  
all the supercell. Both EXX and DFT+U methods localize the electrons  
on two Ti(III) sites neighbouring the missing O because they tend to  
linearize the E(N) vs N curve and, therefore, to create a (correct)  
derivative discontinuity at integer N values in the E(N) curve. They  
also can provide high-spin solutions, and in this regard you are  
right: the correction of delocalization errors by EXX can provide high  
spin results. Regarding the O vacancy, my DFT+U result is a supercell  
with two unpaired electrons on the two Ti(III) sites. They can be  
antiferromagnetically (S=1) or ferromagnetically (S=3) coupled,  
slightly depending on U values, convergence, ...: in chemical language  
they have therefore always the highest multiplicity of electrons, and  
the high-spin and broken-symmetry solutions are very close in energy,  
so close that I'm not really sure about the lowest one, because I've  
not pushed down the forces on nuclei at very very low values. There  
are several papers by Pacchioni, Di Valentin and Selloni where the O  
vacancy has been investigated by using B3LYP in a periodic GTO  
approach. Of course I've not got them here with me, but I (faintly)  
remember that the low-spin solution (two electrons coupled on the same  
Kohn-Sham orbital shared between the same two Ti(III) centers) was  
competitive in energy with the open-shell one far more than in my  
DFT+U calculations, and this fact involves the static correlation  
problem discussed before. The differences between the DFT+U and B3LYP  
total density distributions were minimal, so which is the "correct"  
solution? In my opinion these problems are among the most interesting  
challenges for dft, and I would be very glad to test some mp2 trick on  
correlation like B2PLYP in plane wave calculations...
Sorry for the long answers, and Happy New Year to you!
G.

Giuseppe Mattioli
ISM-CNR
Italy

Quoting Jia Chen :

> Dear Giuseppe,
>
> It is very nice of you to provide so much information! It is certainly much
> more to this question than I thought earlier. Thank you very much and Happy
> New Year.
>
> Cheers
> Jia
>
>
> On Fri, Jan 3, 2014 at 4:27 PM, Giuseppe Mattioli <
> giuseppe.mattioli at ism.cnr.it> wrote:
>
>>
>> Dear Jia
>> Sorry, I'm not at my usual desktop, and I cannot therefore access to
>> the whole of my data base. But I can recall by heart this paper
>> Scherlis, Cococcioni, Sit and Marzari; J. Phys. Chem. B 2007, 111,
>> 7384-7391
>> which investigates the spin states of the well known iron(II)
>> porphyrin and of some of its (Fe(II) and Fe(III)) derivatives. In that
>> case a tendency to stabilize lower-spin states is reported (i.e. in
>> the case of the imidazole or chloride ligated molecules triplet and
>> quartet states arise at the b3lyp level, respectively, as opposite to
>> the expected quintet and sextet states. I've performed calculations
>> (partly unpublished, partly published here,that is, actually, not very
>> visible...)
>> Macroheterocycles 2011 4(3) 161-163
>> on different mono and di-iron porphyrin and phthalocyanine complexes.
>> For instance, in the case of the Fe(III) azide and chloride porphyrins
>> I've obtained a sextet spin-state in the case of DFT+U(Fe=4.0 eV, with
>> Quantum ESPRESSO) and B2PLYP/def2-TZVPP (with the ORCA package), and a
>> quartet spin-state in the case of B3LYP/def2-TZVPP (always with ORCA).
>> More examples: there is an interesting family of Co(III) complexes
>> investigated by several authors (including me). You can find several
>> structures in the supporting information of
>> Li and Siegbahn; J. Am. Chem. Soc. 2013, 135, 13804?13813
>> In the case of the tetranuclear Co(III) complex both B3LYP and
>> DFT+U(Co=5.9 eV,O=2.0 eV) indicate a low spin (S=1) result as the most
>> stable configuration. I've published some results, obtained at a
>> restricted open-shell level on the tetranuclear (something in the SI)
>> and (mainly) on larger complexes here
>> Mattioli et al.; J. Am. Chem. Soc. 2013, 135, 15353?15363
>> The interesting thing (and still under investigation) is that in
>> larger Co(III)-oxo clusters the peripheral Co atoms seem not to couple
>> in a low-spin fashion with the other ones, when investigated at DFT+U
>> level, as opposite to the B3LYP case. If you are interested I can send
>> you some more details offline (after tuesday, however). A very similar
>> tetranuclear Ni-oxo compound has been invest

[Pw_forum] spin polarization of a organo-metallic compound

[Giuseppe Mattioli]

Dear Jia
Sorry, I'm not at my usual desktop, and I cannot therefore access to  
the whole of my data base. But I can recall by heart this paper
Scherlis, Cococcioni, Sit and Marzari; J. Phys. Chem. B 2007, 111, 7384-7391
which investigates the spin states of the well known iron(II)  
porphyrin and of some of its (Fe(II) and Fe(III)) derivatives. In that  
case a tendency to stabilize lower-spin states is reported (i.e. in  
the case of the imidazole or chloride ligated molecules triplet and  
quartet states arise at the b3lyp level, respectively, as opposite to  
the expected quintet and sextet states. I've performed calculations  
(partly unpublished, partly published here,that is, actually, not very  
visible...)
Macroheterocycles 2011 4(3) 161-163
on different mono and di-iron porphyrin and phthalocyanine complexes.  
For instance, in the case of the Fe(III) azide and chloride porphyrins  
I've obtained a sextet spin-state in the case of DFT+U(Fe=4.0 eV, with  
Quantum ESPRESSO) and B2PLYP/def2-TZVPP (with the ORCA package), and a  
quartet spin-state in the case of B3LYP/def2-TZVPP (always with ORCA).
More examples: there is an interesting family of Co(III) complexes  
investigated by several authors (including me). You can find several  
structures in the supporting information of
Li and Siegbahn; J. Am. Chem. Soc. 2013, 135, 13804?13813
In the case of the tetranuclear Co(III) complex both B3LYP and  
DFT+U(Co=5.9 eV,O=2.0 eV) indicate a low spin (S=1) result as the most  
stable configuration. I've published some results, obtained at a  
restricted open-shell level on the tetranuclear (something in the SI)  
and (mainly) on larger complexes here
Mattioli et al.; J. Am. Chem. Soc. 2013, 135, 15353?15363
The interesting thing (and still under investigation) is that in  
larger Co(III)-oxo clusters the peripheral Co atoms seem not to couple  
in a low-spin fashion with the other ones, when investigated at DFT+U  
level, as opposite to the B3LYP case. If you are interested I can send  
you some more details offline (after tuesday, however). A very similar  
tetranuclear Ni-oxo compound has been investigated here
Cao et al.; PRL 100, 167206 (2008)
And a very complex antiferromagnetically-coupled (or broken-symmetry,  
if you prefer) high-spin has been spotted by DFT+U(Ni,O), and  
confirmed by comparison of calculated and measured coupling constants J.

This said, the world of open shell transition metal complexes is vast,  
and of course there is something that does not fit in my previous  
simple solution to Alex's problem. On the other hand, the fact that if  
you stretch an H2 molecule and use EXX you will obtain overcoupling of  
electrons is a matter of fact. Anyway, we may discuss again (after  
next tuesday...) the properties of further compounds.

All the best

Giuseppe

Giuseppe Mattioli
ISM-CNR
Giuseppe





Quoting Jia Chen :

> Dear Giuseppe Mattioli,
>
> It is quite surprising for me, that hybrid functional actually
> overestimates stability of low-spin solution. I know a compound ,for
> which, hybrid functional overestimates stability of high-spin solution. Do
> you know any published papers with examples of hybrid functional favours
> low-spin? Thank you very much!
>
> Bests
> Jia
>
>
> On Fri, Jan 3, 2014 at 2:13 PM, Giuseppe Mattioli <
> giuseppe.mattioli at ism.cnr.it> wrote:
>
>>
>> Dear Alex
>> Paolo is right, of course. Check the convergence on the Re PP first.
>> I would add a few words anyway. Hybrid DFT/HF functionals like B3LYP
>> are pretty useful, but in the case of open-shell systems there are
>> some known limitations. See the very interesting paper by Cohen
>> (Science Vol. 321 no. 5890 pp. 792-794). The HF exchange term added to
>> the DFT xc kernel leads to an overcoupling of electron pairs and,
>> therefore, to an overestimate of the stability of low-spin solutions.
>> Chemists usually call it a "static correlation" error. As we could
>> spend years in discussing such an issue, I feel to suggest two simple
>> tests: try to perform a B2PLYP calculation (if you can afford it) with
>> your GTO package. The MP2 treatment of B3LYP correlation is supposed
>> to correct part of the static correlation error. Otherwise, try to
>> perform a DFT+U calculation with the U correction applied (possibly in
>> a self-consistent fashion, see the many related papers by Cococcioni,
>> De Gironcoli, Kulik, Marzari, and mine) to the Re 5d shell (I did
>> never use Re... Are the 4f electrons embedded in the pseudo?). The
>> on-site DFT+U method is supposed to be free from sce, or, better, less
>> affected than its parent DFT functional. If you obtain a high-spin
>> solution with one of these methods, there are sound reasons, in my
>> opinion, to trust that it is a stable solution...
>> HTH
>> Giuseppe
>>
>> Giuseppe Mattioli
>> ISM-CNR
>> Italy
>>
>> Quoting Alex Granov :
>>
>> > Hi
>> > We are studying an organo-metallic compound which contains 3 Benzene
>> > rings, phosphorous, oxygen, Iodin

[Pw_forum] spin polarization of a organo-metallic compound

[Giuseppe Mattioli]

Dear Alex
Paolo is right, of course. Check the convergence on the Re PP first.
I would add a few words anyway. Hybrid DFT/HF functionals like B3LYP  
are pretty useful, but in the case of open-shell systems there are  
some known limitations. See the very interesting paper by Cohen  
(Science Vol. 321 no. 5890 pp. 792-794). The HF exchange term added to  
the DFT xc kernel leads to an overcoupling of electron pairs and,  
therefore, to an overestimate of the stability of low-spin solutions.  
Chemists usually call it a "static correlation" error. As we could  
spend years in discussing such an issue, I feel to suggest two simple  
tests: try to perform a B2PLYP calculation (if you can afford it) with  
your GTO package. The MP2 treatment of B3LYP correlation is supposed  
to correct part of the static correlation error. Otherwise, try to  
perform a DFT+U calculation with the U correction applied (possibly in  
a self-consistent fashion, see the many related papers by Cococcioni,  
De Gironcoli, Kulik, Marzari, and mine) to the Re 5d shell (I did  
never use Re... Are the 4f electrons embedded in the pseudo?). The  
on-site DFT+U method is supposed to be free from sce, or, better, less  
affected than its parent DFT functional. If you obtain a high-spin  
solution with one of these methods, there are sound reasons, in my  
opinion, to trust that it is a stable solution...
HTH
Giuseppe

Giuseppe Mattioli
ISM-CNR
Italy

Quoting Alex Granov :

> Hi
> We are studying an organo-metallic compound which contains 3 Benzene  
> rings, phosphorous, oxygen, Iodine, and rhenium atoms.Our quantum  
> chemistry study using B3LYP/6-31+G* (Gaussian basis set) shows that  
> the ground state of the system is singlet (spin -unpolarized). We  
> attempted to optimize this structure using quantum espresso to  
> calculate some other electronic properties. Then surprisingly we  
> found that the spin-polarized system is more stable than the  
> spin-unpolarized one in contrast with our quantum chemistry study.  
> In the following you can see my input file and I wonder whether  
> there is something wrong in the input that made the very noticeable  
> contrast. I appreciate your comments to understand the issue and  
> solve it in advance.
> q/e input:&controlcalculation='relax', 
> restart_mode='from_scratch',prefix='Re-Be',pseudo_dir =  
> './pseudo/',outdir='./tmp/',tprnfor=.t. , 
> etot_conv_thr=1.0D-4,forc_conv_thr=1.0D-3,nstep=300, 
> dt=10, / &systemibrav= 8, a=20, b=20, c=20,  nat=37, ntyp=6,  
>ecutwfc = 30, ecutrho = 300, occupations='smearing',  
> smearing='marzari-vanderbilt', degauss=0.005,nspin=2 ,  
> starting_magnetization(1)=1 ,starting_magnetization(2)=1 ,   
> starting_magnetization(3)=1 , starting_magnetization(4)=1 ,  
> starting_magnetization(5)=1 , starting_magnetization(6)=1 , /  
> &electronsconv_thr = 1.0d-6,mixing_beta=0.2, 
> mixing_mode=local-TF, / &IONS  ion_dynamics="bfgs",  upscale=100.0D0  
> ,/ATOMIC_SPECIESRe 186.207  Re.pbe-hgh.UPFO  15.999
> O.pbe-rrkjus.UPFC 12.000C.pbe-rrkjus.UPFH 1.000  
> H.pbe-rrkjus.UPFI 126.90   I.pbe-n-rrkjus_psl.0.2.UPFP  30.9737   
> P.pbe-n-van.UPFK_POINTS {gamma}
>
> -Alex  
> Granov?? ??-???  (MIPT)Moscow, Russia


-- 

- 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: 

[Pw_forum] spin polarization of a organo-metallic compound

[Jia Chen]

Dear Giuseppe,

You are thinking about coupling between magnetic moments. I just wanted to
know if hybrid functional could have non-magnetic ground state, when GGA or
LDA has magnetic ground state. I would like to comment on the difference
between B3LYP and DFT+U. Basically, DFT+U is DFT+Hartree Fock for selected
orbitals and hybrid functional is a mixture of DFT and Hartree. So, it is
not surprising, sometimes, they show similar physics.

Cheers
Jia


On Fri, Jan 3, 2014 at 6:12 PM, Giuseppe Mattioli <
giuseppe.mattioli at ism.cnr.it> wrote:

>
> Dear Jia
> One last (at least for now...) word, which perhaps deserves to be
> written. Let us focus on excess electrons in transition metal oxides
> (only because I've studied them for long). If you create an O vacancy
> in Ti(IV)O2 the missing O atom lets back two excess electrons. If you
> perform a conventional DFT (i.e., PBE) calculation the two excess
> electrons are delocalized in the conduction band and the total
> magnetization is 0 muB. Here the delocalization (self interaction,
> double counting, ...) error spread "little pieces of electron" around
> all the supercell. Both EXX and DFT+U methods localize the electrons
> on two Ti(III) sites neighbouring the missing O because they tend to
> linearize the E(N) vs N curve and, therefore, to create a (correct)
> derivative discontinuity at integer N values in the E(N) curve. They
> also can provide high-spin solutions, and in this regard you are
> right: the correction of delocalization errors by EXX can provide high
> spin results. Regarding the O vacancy, my DFT+U result is a supercell
> with two unpaired electrons on the two Ti(III) sites. They can be
> antiferromagnetically (S=1) or ferromagnetically (S=3) coupled,
> slightly depending on U values, convergence, ...: in chemical language
> they have therefore always the highest multiplicity of electrons, and
> the high-spin and broken-symmetry solutions are very close in energy,
> so close that I'm not really sure about the lowest one, because I've
> not pushed down the forces on nuclei at very very low values. There
> are several papers by Pacchioni, Di Valentin and Selloni where the O
> vacancy has been investigated by using B3LYP in a periodic GTO
> approach. Of course I've not got them here with me, but I (faintly)
> remember that the low-spin solution (two electrons coupled on the same
> Kohn-Sham orbital shared between the same two Ti(III) centers) was
> competitive in energy with the open-shell one far more than in my
> DFT+U calculations, and this fact involves the static correlation
> problem discussed before. The differences between the DFT+U and B3LYP
> total density distributions were minimal, so which is the "correct"
> solution? In my opinion these problems are among the most interesting
> challenges for dft, and I would be very glad to test some mp2 trick on
> correlation like B2PLYP in plane wave calculations...
> Sorry for the long answers, and Happy New Year to you!
> G.
>
> Giuseppe Mattioli
> ISM-CNR
> Italy
>
> Quoting Jia Chen :
>
> > Dear Giuseppe,
> >
> > It is very nice of you to provide so much information! It is certainly
> much
> > more to this question than I thought earlier. Thank you very much and
> Happy
> > New Year.
> >
> > Cheers
> > Jia
> >
> >
> > On Fri, Jan 3, 2014 at 4:27 PM, Giuseppe Mattioli <
> > giuseppe.mattioli at ism.cnr.it> wrote:
> >
> >>
> >> Dear Jia
> >> Sorry, I'm not at my usual desktop, and I cannot therefore access to
> >> the whole of my data base. But I can recall by heart this paper
> >> Scherlis, Cococcioni, Sit and Marzari; J. Phys. Chem. B 2007, 111,
> >> 7384-7391
> >> which investigates the spin states of the well known iron(II)
> >> porphyrin and of some of its (Fe(II) and Fe(III)) derivatives. In that
> >> case a tendency to stabilize lower-spin states is reported (i.e. in
> >> the case of the imidazole or chloride ligated molecules triplet and
> >> quartet states arise at the b3lyp level, respectively, as opposite to
> >> the expected quintet and sextet states. I've performed calculations
> >> (partly unpublished, partly published here,that is, actually, not very
> >> visible...)
> >> Macroheterocycles 2011 4(3) 161-163
> >> on different mono and di-iron porphyrin and phthalocyanine complexes.
> >> For instance, in the case of the Fe(III) azide and chloride porphyrins
> >> I've obtained a sextet spin-state in the case of DFT+U(Fe=4.0 eV, with
> >> Quantum ESPRESSO) and B2PLYP/def2-TZVPP (with the ORCA package), and a
> >> quartet spin-state in the case of B3LYP/def2-TZVPP (always with ORCA).
> >> More examples: there is an interesting family of Co(III) complexes
> >> investigated by several authors (including me). You can find several
> >> structures in the supporting information of
> >> Li and Siegbahn; J. Am. Chem. Soc. 2013, 135, 13804?13813
> >> In the case of the tetranuclear Co(III) complex both B3LYP and
> >> DFT+U(Co=5.9 eV,O=2.0 eV) indicate a low spin (S=1) result as the most
>

[Pw_forum] spin polarization of a organo-metallic compound

[Jia Chen]

Dear Giuseppe,

It is very nice of you to provide so much information! It is certainly much
more to this question than I thought earlier. Thank you very much and Happy
New Year.

Cheers
Jia


On Fri, Jan 3, 2014 at 4:27 PM, Giuseppe Mattioli <
giuseppe.mattioli at ism.cnr.it> wrote:

>
> Dear Jia
> Sorry, I'm not at my usual desktop, and I cannot therefore access to
> the whole of my data base. But I can recall by heart this paper
> Scherlis, Cococcioni, Sit and Marzari; J. Phys. Chem. B 2007, 111,
> 7384-7391
> which investigates the spin states of the well known iron(II)
> porphyrin and of some of its (Fe(II) and Fe(III)) derivatives. In that
> case a tendency to stabilize lower-spin states is reported (i.e. in
> the case of the imidazole or chloride ligated molecules triplet and
> quartet states arise at the b3lyp level, respectively, as opposite to
> the expected quintet and sextet states. I've performed calculations
> (partly unpublished, partly published here,that is, actually, not very
> visible...)
> Macroheterocycles 2011 4(3) 161-163
> on different mono and di-iron porphyrin and phthalocyanine complexes.
> For instance, in the case of the Fe(III) azide and chloride porphyrins
> I've obtained a sextet spin-state in the case of DFT+U(Fe=4.0 eV, with
> Quantum ESPRESSO) and B2PLYP/def2-TZVPP (with the ORCA package), and a
> quartet spin-state in the case of B3LYP/def2-TZVPP (always with ORCA).
> More examples: there is an interesting family of Co(III) complexes
> investigated by several authors (including me). You can find several
> structures in the supporting information of
> Li and Siegbahn; J. Am. Chem. Soc. 2013, 135, 13804?13813
> In the case of the tetranuclear Co(III) complex both B3LYP and
> DFT+U(Co=5.9 eV,O=2.0 eV) indicate a low spin (S=1) result as the most
> stable configuration. I've published some results, obtained at a
> restricted open-shell level on the tetranuclear (something in the SI)
> and (mainly) on larger complexes here
> Mattioli et al.; J. Am. Chem. Soc. 2013, 135, 15353?15363
> The interesting thing (and still under investigation) is that in
> larger Co(III)-oxo clusters the peripheral Co atoms seem not to couple
> in a low-spin fashion with the other ones, when investigated at DFT+U
> level, as opposite to the B3LYP case. If you are interested I can send
> you some more details offline (after tuesday, however). A very similar
> tetranuclear Ni-oxo compound has been investigated here
> Cao et al.; PRL 100, 167206 (2008)
> And a very complex antiferromagnetically-coupled (or broken-symmetry,
> if you prefer) high-spin has been spotted by DFT+U(Ni,O), and
> confirmed by comparison of calculated and measured coupling constants J.
>
> This said, the world of open shell transition metal complexes is vast,
> and of course there is something that does not fit in my previous
> simple solution to Alex's problem. On the other hand, the fact that if
> you stretch an H2 molecule and use EXX you will obtain overcoupling of
> electrons is a matter of fact. Anyway, we may discuss again (after
> next tuesday...) the properties of further compounds.
>
> All the best
>
> Giuseppe
>
> Giuseppe Mattioli
> ISM-CNR
> Giuseppe
>
>
>
>
>
> Quoting Jia Chen :
>
> > Dear Giuseppe Mattioli,
> >
> > It is quite surprising for me, that hybrid functional actually
> > overestimates stability of low-spin solution. I know a compound ,for
> > which, hybrid functional overestimates stability of high-spin solution.
> Do
> > you know any published papers with examples of hybrid functional favours
> > low-spin? Thank you very much!
> >
> > Bests
> > Jia
> >
> >
> > On Fri, Jan 3, 2014 at 2:13 PM, Giuseppe Mattioli <
> > giuseppe.mattioli at ism.cnr.it> wrote:
> >
> >>
> >> Dear Alex
> >> Paolo is right, of course. Check the convergence on the Re PP first.
> >> I would add a few words anyway. Hybrid DFT/HF functionals like B3LYP
> >> are pretty useful, but in the case of open-shell systems there are
> >> some known limitations. See the very interesting paper by Cohen
> >> (Science Vol. 321 no. 5890 pp. 792-794). The HF exchange term added to
> >> the DFT xc kernel leads to an overcoupling of electron pairs and,
> >> therefore, to an overestimate of the stability of low-spin solutions.
> >> Chemists usually call it a "static correlation" error. As we could
> >> spend years in discussing such an issue, I feel to suggest two simple
> >> tests: try to perform a B2PLYP calculation (if you can afford it) with
> >> your GTO package. The MP2 treatment of B3LYP correlation is supposed
> >> to correct part of the static correlation error. Otherwise, try to
> >> perform a DFT+U calculation with the U correction applied (possibly in
> >> a self-consistent fashion, see the many related papers by Cococcioni,
> >> De Gironcoli, Kulik, Marzari, and mine) to the Re 5d shell (I did
> >> never use Re... Are the 4f electrons embedded in the pseudo?). The
> >> on-site DFT+U method is supposed to be free from sce, or, better, less

[Pw_forum] spin polarization of a organo-metallic compound

[Jia Chen]

Dear Giuseppe Mattioli,

It is quite surprising for me, that hybrid functional actually
overestimates stability of low-spin solution. I know a compound ,for
which, hybrid functional overestimates stability of high-spin solution. Do
you know any published papers with examples of hybrid functional favours
low-spin? Thank you very much!

Bests
Jia


On Fri, Jan 3, 2014 at 2:13 PM, Giuseppe Mattioli <
giuseppe.mattioli at ism.cnr.it> wrote:

>
> Dear Alex
> Paolo is right, of course. Check the convergence on the Re PP first.
> I would add a few words anyway. Hybrid DFT/HF functionals like B3LYP
> are pretty useful, but in the case of open-shell systems there are
> some known limitations. See the very interesting paper by Cohen
> (Science Vol. 321 no. 5890 pp. 792-794). The HF exchange term added to
> the DFT xc kernel leads to an overcoupling of electron pairs and,
> therefore, to an overestimate of the stability of low-spin solutions.
> Chemists usually call it a "static correlation" error. As we could
> spend years in discussing such an issue, I feel to suggest two simple
> tests: try to perform a B2PLYP calculation (if you can afford it) with
> your GTO package. The MP2 treatment of B3LYP correlation is supposed
> to correct part of the static correlation error. Otherwise, try to
> perform a DFT+U calculation with the U correction applied (possibly in
> a self-consistent fashion, see the many related papers by Cococcioni,
> De Gironcoli, Kulik, Marzari, and mine) to the Re 5d shell (I did
> never use Re... Are the 4f electrons embedded in the pseudo?). The
> on-site DFT+U method is supposed to be free from sce, or, better, less
> affected than its parent DFT functional. If you obtain a high-spin
> solution with one of these methods, there are sound reasons, in my
> opinion, to trust that it is a stable solution...
> HTH
> Giuseppe
>
> Giuseppe Mattioli
> ISM-CNR
> Italy
>
> Quoting Alex Granov :
>
> > Hi
> > We are studying an organo-metallic compound which contains 3 Benzene
> > rings, phosphorous, oxygen, Iodine, and rhenium atoms.Our quantum
> > chemistry study using B3LYP/6-31+G* (Gaussian basis set) shows that
> > the ground state of the system is singlet (spin -unpolarized). We
> > attempted to optimize this structure using quantum espresso to
> > calculate some other electronic properties. Then surprisingly we
> > found that the spin-polarized system is more stable than the
> > spin-unpolarized one in contrast with our quantum chemistry study.
> > In the following you can see my input file and I wonder whether
> > there is something wrong in the input that made the very noticeable
> > contrast. I appreciate your comments to understand the issue and
> > solve it in advance.
> > q/e input:&controlcalculation='relax',
> > restart_mode='from_scratch',prefix='Re-Be',pseudo_dir =
> > './pseudo/',outdir='./tmp/',tprnfor=.t. ,
> > etot_conv_thr=1.0D-4,forc_conv_thr=1.0D-3,nstep=300,
> > dt=10, / &systemibrav= 8, a=20, b=20, c=20,  nat=37, ntyp=6,
> >ecutwfc = 30, ecutrho = 300, occupations='smearing',
> > smearing='marzari-vanderbilt', degauss=0.005,nspin=2 ,
> > starting_magnetization(1)=1 ,starting_magnetization(2)=1 ,
> > starting_magnetization(3)=1 , starting_magnetization(4)=1 ,
> > starting_magnetization(5)=1 , starting_magnetization(6)=1 , /
> > &electronsconv_thr = 1.0d-6,mixing_beta=0.2,
> > mixing_mode=local-TF, / &IONS  ion_dynamics="bfgs",  upscale=100.0D0
> > ,/ATOMIC_SPECIESRe 186.207  Re.pbe-hgh.UPFO  15.999
> > O.pbe-rrkjus.UPFC 12.000C.pbe-rrkjus.UPFH 1.000
> > H.pbe-rrkjus.UPFI 126.90   I.pbe-n-rrkjus_psl.0.2.UPFP  30.9737
> > P.pbe-n-van.UPFK_POINTS {gamma}
> >
> > -Alex
> > Granov?? ??-???  (MIPT)Moscow, Russia
>
>
> --
> 
> - 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: 
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 
Jia Chen
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[Pw_forum] spin polarization of a organo-metallic compound

[Paolo Giannozzi]

On Thu, 2014-01-02 at 21:31 +, Alex Granov wrote:

> Re 186.207  Re.pbe-hgh.UPF

This is a norm-conserving pseudopotential. While very
accurate, these pseudopotentials are very hard. A 30 Ry
cutoff might be way too small.

P.
-- 
Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222 

[Pw_forum] spin polarization of a organo-metallic compound

[Alex Granov]

Hi
We are studying an organo-metallic compound which contains 3 Benzene rings, 
phosphorous, oxygen, Iodine, and rhenium atoms.Our quantum chemistry study 
using B3LYP/6-31+G* (Gaussian basis set) shows that the ground state of the 
system is singlet (spin -unpolarized). We attempted to optimize this structure 
using quantum espresso to calculate some other electronic properties. Then 
surprisingly we found that the spin-polarized system is more stable than the 
spin-unpolarized one in contrast with our quantum chemistry study. In the 
following you can see my input file and I wonder whether there is something 
wrong in the input that made the very noticeable contrast. I appreciate your 
comments to understand the issue and solve it in advance. 
q/e input:&controlcalculation='relax',restart_mode='from_scratch',
prefix='Re-Be',pseudo_dir = './pseudo/',outdir='./tmp/',tprnfor=.t. 
,etot_conv_thr=1.0D-4,forc_conv_thr=1.0D-3,nstep=300,dt=10, 
/ &systemibrav= 8, a=20, b=20, c=20,  nat=37, ntyp=6,ecutwfc = 30, 
ecutrho = 300, occupations='smearing', smearing='marzari-vanderbilt', 
degauss=0.005,nspin=2 , starting_magnetization(1)=1 
,starting_magnetization(2)=1 ,  starting_magnetization(3)=1 , 
starting_magnetization(4)=1 , starting_magnetization(5)=1 , 
starting_magnetization(6)=1 , / &electronsconv_thr = 1.0d-6,
mixing_beta=0.2,mixing_mode=local-TF, / &IONS  ion_dynamics="bfgs",  
upscale=100.0D0 ,/ATOMIC_SPECIESRe 186.207  Re.pbe-hgh.UPFO  15.999   
O.pbe-rrkjus.UPFC 12.000C.pbe-rrkjus.UPFH 1.000 H.pbe-rrkjus.UPFI 
126.90   I.pbe-n-rrkjus_psl.0.2.UPFP  30.9737  P.pbe-n-van.UPFK_POINTS {gamma}  
  

-Alex Granov?? 
??-???  (MIPT)Moscow, Russia
   
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[Pw_forum] spin orbit and custom occupations

[Andrea Dal Corso]

With spin-orbit coupling states are not eigenstates of S_z,
so one cannot separate spin up and spin down. 
However when spin-orbit is small and magnetization is large the states
can be mainly spin up or mainly spin down and you can see this by
calculating the expectation value of \sigma_z (if the magnetization is
along z). This can be done with the band.x program.

HTH,

Andrea 

On Thu, 2013-09-26 at 18:33 +0200, Julen Larrucea wrote:
> Thanks Andrea,
> 
> 
> but this doesn't really solve my problem...
> 
> 
> I still can't find from example06 how to check the final occupations.
> 
> If I use nspin=4, which is supposed to be spin-polarized, unlike in
> the case of nspin=2, I only get a single row of occupations, like this
> 
>  occupation numbers 
>  1.   1.   1.   1.   1.   1.   1.
> 1.
>  1.   1.   1.   1.   1.   1.0001   0.9219
> 0.1150
> -0.0167  -0.0202   0.   0.   0.   0.   0.
> 0.
> 
> 
> But which of them are up or down? or, how can I find out whether I
> have a singlet or a triplet in my single isolated atom?
> 
> 
>   Thanks in advance
> 
> 
>  Julen
> 
> 
> 
> 
> 
> On Wed, Sep 25, 2013 at 2:31 PM, Andrea Dal Corso 
> wrote:
> constrained_magnetization='total'
> 
> allows you to fix the magnetization vector. See example06 for
> more
> details.
> 
> HTH,
> 
> Andrea
> 
> 
> 
> On Wed, 2013-09-25 at 11:51 +0200, Julen Larrucea wrote:
> > Dear colleagues,
> > Does anybody know how to set precisely the occupations on a
> spin orbit
> > calculation (lspinorb=.true.)?
> >
> > I have tried to occupations='from_input' but it does not
> read the
> > minority spin line, and constrained- and tot_magnetization
> do not seem
> > to work either.
> >
> >
> >   Thanks in advance
> >
> >
> > Julen
> > --
> > Dr. Julen Larrucea
> > Postdoctoral researcher,
> > BCCMS, HMI Group, University of Bremen
> > Phone: +49 421 218 64582
> > Fax: +49 421 218 64599
> >  http://www.larrucea.eu
> 
> > ___
> > Pw_forum mailing list
> > Pw_forum at pwscf.org
> > http://pwscf.org/mailman/listinfo/pw_forum
> --
> Andrea Dal CorsoTel. 0039-040-3787428
> SISSA, Via Bonomea 265  Fax. 0039-040-3787249
> I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it
> 
> 
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
> 
> 
> 
> -- 
> -- 
> Dr. Julen Larrucea
> Postdoctoral researcher,
> BCCMS, HMI Group, University of Bremen
> Phone: +49 421 218 64582
> Fax: +49 421 218 64599
>  http://www.larrucea.eu
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
-- 
Andrea Dal CorsoTel. 0039-040-3787428
SISSA, Via Bonomea 265  Fax. 0039-040-3787249
I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it

[Pw_forum] spin orbit and custom occupations

[Julen Larrucea]

Thanks Andrea,

but this doesn't really solve my problem...

I still can't find from example06 how to check the final occupations.
If I use nspin=4, which is supposed to be spin-polarized, unlike in the
case of nspin=2, I only get a single row of occupations, like this

 occupation numbers
 1.   1.   1.   1.   1.   1.   1.   1.
 1.   1.   1.   1.   1.   1.0001   0.9219   0.1150
-0.0167  -0.0202   0.   0.   0.   0.   0.   0.

But which of them are up or down? or, how can I find out whether I have a
singlet or a triplet in my single isolated atom?

  Thanks in advance

 Julen



On Wed, Sep 25, 2013 at 2:31 PM, Andrea Dal Corso  wrote:

> constrained_magnetization='total'
>
> allows you to fix the magnetization vector. See example06 for more
> details.
>
> HTH,
>
> Andrea
>
>
>
> On Wed, 2013-09-25 at 11:51 +0200, Julen Larrucea wrote:
> > Dear colleagues,
> > Does anybody know how to set precisely the occupations on a spin orbit
> > calculation (lspinorb=.true.)?
> >
> > I have tried to occupations='from_input' but it does not read the
> > minority spin line, and constrained- and tot_magnetization do not seem
> > to work either.
> >
> >
> >   Thanks in advance
> >
> >
> > Julen
> > --
> > Dr. Julen Larrucea
> > Postdoctoral researcher,
> > BCCMS, HMI Group, University of Bremen
> > Phone: +49 421 218 64582
> > Fax: +49 421 218 64599
> >  http://www.larrucea.eu
> > ___
> > Pw_forum mailing list
> > Pw_forum at pwscf.org
> > http://pwscf.org/mailman/listinfo/pw_forum
> --
> Andrea Dal CorsoTel. 0039-040-3787428
> SISSA, Via Bonomea 265  Fax. 0039-040-3787249
> I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 

-- 
Dr. Julen Larrucea
Postdoctoral researcher,
BCCMS, HMI Group, University of Bremen
Phone: +49 421 218 64582
Fax: +49 421 218 64599
 http://www.larrucea.eu
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[Pw_forum] spin orbit and custom occupations

[Andrea Dal Corso]

constrained_magnetization='total'

allows you to fix the magnetization vector. See example06 for more
details. 

HTH,

Andrea



On Wed, 2013-09-25 at 11:51 +0200, Julen Larrucea wrote:
> Dear colleagues,
> Does anybody know how to set precisely the occupations on a spin orbit
> calculation (lspinorb=.true.)?
> 
> I have tried to occupations='from_input' but it does not read the
> minority spin line, and constrained- and tot_magnetization do not seem
> to work either.
> 
> 
>   Thanks in advance
> 
> 
> Julen
> -- 
> Dr. Julen Larrucea
> Postdoctoral researcher,
> BCCMS, HMI Group, University of Bremen
> Phone: +49 421 218 64582
> Fax: +49 421 218 64599
>  http://www.larrucea.eu
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
-- 
Andrea Dal CorsoTel. 0039-040-3787428
SISSA, Via Bonomea 265  Fax. 0039-040-3787249
I-34136 Trieste (Italy) e-mail: dalcorso at sissa.it

[Pw_forum] spin orbit and custom occupations

[Julen Larrucea]

Dear colleagues,
Does anybody know how to set precisely the occupations on a spin orbit
calculation (lspinorb=.true.)?
I have tried to occupations='from_input' but it does not read the minority
spin line, and constrained- and tot_magnetization do not seem to work
either.

  Thanks in advance

Julen

-- 
Dr. Julen Larrucea
Postdoctoral researcher,
BCCMS, HMI Group, University of Bremen
Phone: +49 421 218 64582
Fax: +49 421 218 64599
 http://www.larrucea.eu
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[Pw_forum] Spin-Unrestricted Calculation for O2 Adsorption

[Paolo Giannozzi]

On Tue, 2013-05-07 at 19:28 -0400, Vic Bermudez wrote:

> starting_magnetization=0.17

should be starting_magnetization(1)=0.17
and should not be needed if option

> occupations='from_input'

is present. In general: either you set the
occupations or the total magnetization,
or you set them free and give a starting
magnetization to break the symmetry

P/
-- 
 Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
 Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
 Phone +39-0432-558216, fax +39-0432-558222 

[Pw_forum] Spin-Unrestricted Calculation for O2 Adsorption

[Nicola Marzari]

Dear Vic,


I think you could just specify the total_magnetization, and if the 
surface is metallic, or magnetic, use also smearing?

nicola


On 08/05/2013 01:28, Vic Bermudez wrote:
> Hello,
>
>   I want to do a calculation for O2 (in its triplet ground state) 
> adsorbing
> on a surface. The surface, as usual, is modeled using a two-dimensional slab
> supercell. For the free O2 molecule I know how to treat the triplet ground
> state using
>
> &SYSTEM
> .
> .
> nspin=2,
> starting_magnetization=0.17,
> nband=8,
> occupations='from_input',
> .
> .
> /
>
> OCCUPATIONS
> 1 1 1 1 1 1 1 0
> 1 1 1 1 1 0 0 0
>
>
>   What I don't know is how to extend this type of input to the adsorption
> case. It doesn't seem practical to specify "nband" and "occupations" for the
> entire supercell + O2. There has to be a better way, but I haven't been able
> to find anything in the documentation or at the users' forum.
>   Any help would be much appreciated.
>
> Thanks,
> Vic Bermudez
>
>
> Victor M. Bermudez
> Code 6876
> U.S. Naval Research Laboratory
> 4555 Overlook Ave., S.W.
> Washington, DC 20375-5347
>
>Phone: 202-767-6728
>FAX: 202-767-1165
>E-mail: victor.bermudez at nrl.navy.mil
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>


-- 

--
Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL

[Pw_forum] Spin-Unrestricted Calculation for O2 Adsorption

[Vic Bermudez]

Hello,

I want to do a calculation for O2 (in its triplet ground state) 
adsorbing
on a surface. The surface, as usual, is modeled using a two-dimensional slab
supercell. For the free O2 molecule I know how to treat the triplet ground
state using

&SYSTEM
.
.
nspin=2,
starting_magnetization=0.17,
nband=8,
occupations='from_input',
.
.
/

OCCUPATIONS
1 1 1 1 1 1 1 0
1 1 1 1 1 0 0 0


What I don't know is how to extend this type of input to the adsorption
case. It doesn't seem practical to specify "nband" and "occupations" for the
entire supercell + O2. There has to be a better way, but I haven't been able
to find anything in the documentation or at the users' forum.
Any help would be much appreciated.

Thanks,
Vic Bermudez


Victor M. Bermudez
Code 6876
U.S. Naval Research Laboratory
4555 Overlook Ave., S.W.
Washington, DC 20375-5347

  Phone: 202-767-6728
  FAX: 202-767-1165
  E-mail: victor.bermudez at nrl.navy.mil

[Pw_forum] Spin Polarised Transport

[Alex Smogunov]

Dear Dave.
Of course you can use it, everybody can, especially for spin polarized
transport. The choice depends on the size of your system.
regards,
Alexander



2013/4/12 Mugdha Dave 

> Hello All,
>
> I want to do spin polarized transport using pw.cond. I want to know
> whether setting nspin =2 does spin polarized calculation or spin
> contribution to transport.Is pw.scf good choice for this? Or I should opt
> for siesta or other codes?
>
> Thanks
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
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[Pw_forum] Spin Polarised Transport

[Mugdha Dave]

Hello All,

I want to do spin polarized transport using pw.cond. I
 want to know whether setting nspin =2 does spin polarized calculation 
or spin contribution to transport.Is pw.scf good choice for this? Or I 
should opt for siesta or other codes?? 

Thanks 
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[Pw_forum] spin polarised transport

[Mugdha Dave]

Hello All,

I want to do spin polarized transport using pw.cond. I want to know whether 
setting nspin =2 does spin polarized calculation or spin contribution to 
transport.Is pw.scf good choice for this? Or I should opt for siesta or other 
codes?? 

Thanks 

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[Pw_forum] spin direction

[Giuseppe Mattioli]

It seems you've already done it... Sorry!

On Thursday 20 September 2012 21:15:06 Peng Chen wrote:
> Dear All,
> 
> In the Quantum Espresso, can I specify spin direction? E.g, in the unit
> cell, spins of M1 and M2 are along c direction (spin of M1 is opposite to
> that of M2), whereas spins of M3 and M4 are in b direction. Can I simulate
> this magnetic structure in QE? Thank you in advance for any help you can
> provide.

-- 

- 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: 

[Pw_forum] spin direction

[Giuseppe Mattioli]

Dear Peng
Look at the PW_INPUT documentation ("noncolin" variable and related quantities) 
and at example06 in 
the PW dir.
HTH
Giuseppe

On Thursday 20 September 2012 21:15:06 Peng Chen wrote:
> Dear All,
> 
> In the Quantum Espresso, can I specify spin direction? E.g, in the unit
> cell, spins of M1 and M2 are along c direction (spin of M1 is opposite to
> that of M2), whereas spins of M3 and M4 are in b direction. Can I simulate
> this magnetic structure in QE? Thank you in advance for any help you can
> provide.

-- 

- 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: 

[Pw_forum] spin direction

[Peng Chen]

Dear Dr.  Giannozzi,

Thanks for your note! In some afm structures, there is "spin canting" due
to the  Dzyaloshinskii-Moriya interaction. Does noncolinear magnetization
calculation in QE involve spin canting effect?

I also tried to use LDA+U with noncolinear magnetization calculation, but
it only works for lda_plus_u_kind=1. In that case, I don't know what is the
value of Hubbard_J . Whereas, when lda_plus_u_kind=0, the U can be computed
by linear-response method of Cococcioni et al.. So can I consider
lda_plus_u_kind=0 is the same condition as:  lda_plus_u_kind=1 and
 Hubbard_J = 0?

On Thu, Sep 20, 2012 at 3:35 PM, Paolo Giannozzi wrote:

>
> On Sep 20, 2012, at 21:15 , Peng Chen wrote:
>
> > In the Quantum Espresso, can I specify spin direction? E.g, in the
> > unit cell, spins of M1 and M2 are along c direction (spin of M1 is
> > opposite to that of M2), whereas spins of M3 and M4 are in b
> > direction. Can I simulate this magnetic structure in QE?
>
> yes, it is called "noncolinear magnetization"
>
> P.
> ---
> Paolo Giannozzi, Dept of Chemistry&Physics&Environment,
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222
>
>
>
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>



-- 
  Best Regards.
Peng
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[Pw_forum] spin direction

[Paolo Giannozzi]

On Sep 20, 2012, at 21:15 , Peng Chen wrote:

> In the Quantum Espresso, can I specify spin direction? E.g, in the  
> unit cell, spins of M1 and M2 are along c direction (spin of M1 is  
> opposite to that of M2), whereas spins of M3 and M4 are in b  
> direction. Can I simulate this magnetic structure in QE?

yes, it is called "noncolinear magnetization"

P.
---
Paolo Giannozzi, Dept of Chemistry&Physics&Environment,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222

[Pw_forum] spin direction

[Peng Chen]

Dear All,

In the Quantum Espresso, can I specify spin direction? E.g, in the unit
cell, spins of M1 and M2 are along c direction (spin of M1 is opposite to
that of M2), whereas spins of M3 and M4 are in b direction. Can I simulate
this magnetic structure in QE? Thank you in advance for any help you can
provide.

-- 
  Best Regards.
Peng
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[Pw_forum] Spin polarization of Graphene

[Rahen Badsha]

Dear QE users,
I am a researcher on graphene. 

I want to calculate the spin polarization of graphene. 

What will be the input code(i.e. scf, nscf, band, plotband and dos) of graphene 
as a spintronic material?
How can I progress? 

What is the amount of percent of spin polarization of graphene?


Please help me.


Regards-
Rahen Badsha (Raihan)
A post graduate thesis student
University of Rajshahi, Bangladesh.
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[Pw_forum] spin density plot in real space

[Axel Kohlmeyer]

On Mon, Dec 12, 2011 at 12:11 AM, Padmaja Patnaik
 wrote:
> Dear All
>
> I have a doubt regarding density plot. How can we plot the spin density in
> real space?

the difference between the spin up and spin down densities?

axel


> Thanks in advance
> regards,
>
> Padmaja Patnaik
> Research Scholar
> Dept of Physics
> IIT Bombay
> Mumbai, India
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>



-- 
Dr. Axel Kohlmeyer
akohlmey at gmail.com ?http://goo.gl/1wk0

College of Science and Technology
Temple University, Philadelphia PA, USA.

[Pw_forum] spin density plot in real space

[Padmaja Patnaik]

Dear All

I have a doubt regarding density plot. How can we plot the spin density in real 
space?

Thanks in advance
regards,

?
Padmaja Patnaik
Research Scholar
Dept of Physics
IIT Bombay
Mumbai, India
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[Pw_forum] Spin polarization

[Éric Germaneau]

Dear all,

I work on Boron Nitride structures and got confused about the use spin 
polarization in that case.
Well, some people say that one have to but I have papers which described 
DFT calculations on BN without it.
So, I'm wondering how much spin polarization influence the cell 
relaxation and scf calculations, and whether it has some influence on 
phonon for instance.
Thank you,

   ?ric.

-- 
/Be the change you wish to see in the world
/ --- Mahatma Gandhi ---

Dr. ?ric Germaneau 


Graduate University of Chinese Academy of Sciences
College of Physical Sciences
Yuquan Road 19A
Beijing 100049
China

/Please, if possible, don't send me MS Word or PowerPoint attachments
Why? See: http://www.gnu.org/philosophy/no-word-attachments.html /

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[Pw_forum] spin polarised STM

[Guido Fratesi]

Dear Madhura,

> 1. While calculating STM image, is sum taken over both the spin
> channels? Because there is no option for spin resolved calculations,
> and in the subroutine I was not able to find where sum is done.?

Yes it is. The sum is taken over all k-points, regardless of the spin this 
kpoint correspond to (as you know, in pwscf spin "up" and spin "down" are 
treated as two sets of kpoints).

> 2. Does anyone have a subroutine to get spin-polarized STM image? If
> yes, can you send it?

You might consider using again pp.x to plot the ILDOS in the corresponding 
energy range, for which you can specify the spin component. Although the 
weight of states contributing to ILDOS and STM is not computed exactly in 
the same way by pp.x, you should expect the results to become equivalent 
as the number of relevant states falling in the energy interval is 
sufficiently large (see, number of kpoints & slab thickness).

> 3. Or if not, can anyone tell which part of code needs to be modified
> to get SP-STM image?

At line 150 of PP/stm.f90, "DO ik = 1, nks". You could restrict this 
summation to states with wanted spin, or accumulate the two sums 
independently. The spin of each kpoint is stored in isk(ik). See its use 
in projwfc.f90 for examples.

HTH

-- 
Guido Fratesi

Dipartimento di Scienza dei Materiali
Universita` degli Studi di Milano-Bicocca
via Cozzi 53, 20125 Milano, Italy

[Pw_forum] spin polarised STM

[madh...@jncasr.ac.in]

Dear all,

I have done some spin polarized calculations, and would like to get
STM image for the system. Now I have a few questions regarding this PP
tool:

1. While calculating STM image, is sum taken over both the spin
channels? Because there is no option for spin resolved calculations,
and in the subroutine I was not able to find where sum is done.? 

2. Does anyone have a subroutine to get spin-polarized STM image? If
yes, can you send it? 

3. Or if not, can anyone tell which part of code needs to be modified
to get SP-STM image? 

Thanks a lot,
Madhura.


PhD Student,
Theoretical Sciences Unit, 
JNCASR, Bangalore - 560064.
Ph. No. +91 80 2208 2835


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[Pw_forum] spin-orbit coupling

[Julen Ibanez Azpiroz]

Dear Peiman,

As far as I know, in QE the spin-orbit coupling is taken into account by
fully relativistic pseudopotentials, so you have to build this kind of PP
for your atoms. Once you have them, I think that the way to include the it
is to set lspinorb=.true. and also noncolin=.true.

Best regards

Julen Iba?ez

University of the Basque Country, Condensed Matter Physics
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[Pw_forum] spin-orbit coupling

[peyman amiri]

Dear all
I want to apply the spin-orbit coupling in my system so I have some questions.
1. How can i choose the amount of spin-orbit interaction in my system?
2. For this purpose do i need to choose options nspin=2? or? noncolin=.true. ?
Any suggestion will be appreciated


==

Peiman Amiri

Computational Condensed Matter Research Lab

Physics Department, Isfahan University of Technology, Iran

  

Tel lab: +98 311 391 3733Fax Office: +98311 391 3746 

--


  
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[Pw_forum] spin-polarized results error

[Fen Hong]

Dear all,
I was trying to calculate Au atom with spin-polarized by norm-conserving
scalar relativistic pseudopotential.
The Au configuration is 5d106s1.
I thought it would give the result 1, while what I got is "
 total magnetization   = 0.00 Bohr mag/cell
 absolute magnetization= 0.00 Bohr mag/cell
"  Could anyone give me some tips about this or I misunderstand something.
Thank you very much.
the Input
&CONTROL
  calculation= "relax",
  prefix = "Au-30"
  nstep  = 500,
  pseudo_dir   = "/home/Au",
  outdir   = "/scr/",
/
&SYSTEM
  ibrav  = 4,
  celldm(1)  = 33.123112,
  celldm(3)  = 1.42628937,
  nat= 1,
  ntyp   = 1,
  ecutwfc= 30.0D0,
  nspin  = 2,
  starting_magnetization(1) = 0.2,
  occupations  = "smearing",
  degauss  = 0.05,
/
&ELECTRONS
  conv_thr= 1.0D-8,
  mixing_beta = 0.3D0,
  electron_maxstep = 400,
/
&IONS
  ds= 1.D-8,
/
ATOMIC_SPECIES
Au 196.96655Au-wc.UPF
ATOMIC_POSITIONS { angstrom }
Au  3.755923000  7.951333000  7.475759000
K_POINTS {gamma}

Best wishes,
Gao Min
Japan
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[Pw_forum] spin-polarized results error

[Gabriele Sclauzero]

Most probably your smearing parameter is too large or you need to break 
symmetry somehow. What you can do is to perform two calculations with 
occupations="from_input" and fix the occupations corresponding to a magnetic 
solution and a non-magnetic solution. Then compare the total energies.

HTH


GS

Il giorno 13/gen/2011, alle ore 04.37, Fen Hong ha scritto:

> Dear all,
> I was trying to calculate Au atom with spin-polarized by norm-conserving 
> scalar relativistic pseudopotential.
> The Au configuration is 5d106s1.
> I thought it would give the result 1, while what I got is "   
>  total magnetization   = 0.00 Bohr mag/cell
>  absolute magnetization= 0.00 Bohr mag/cell
> "  Could anyone give me some tips about this or I misunderstand something. 
> Thank you very much.
> the Input 
> &CONTROL
>   calculation= "relax",
>   prefix = "Au-30"
>   nstep  = 500,
>   pseudo_dir   = "/home/Au",
>   outdir   = "/scr/",
> /
> &SYSTEM
>   ibrav  = 4,
>   celldm(1)  = 33.123112,
>   celldm(3)  = 1.42628937,
>   nat= 1,
>   ntyp   = 1,
>   ecutwfc= 30.0D0,
>   nspin  = 2,
>   starting_magnetization(1) = 0.2,
>   occupations  = "smearing",
>   degauss  = 0.05,
> /
> &ELECTRONS
>   conv_thr= 1.0D-8,
>   mixing_beta = 0.3D0,
>   electron_maxstep = 400,
> /
> &IONS
>   ds= 1.D-8,
> /
> ATOMIC_SPECIES
> Au 196.96655Au-wc.UPF
> ATOMIC_POSITIONS { angstrom }
> Au  3.755923000  7.951333000  7.475759000
> K_POINTS {gamma}
> 
> Best wishes,
> Gao Min
> Japan
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum


? Gabriele Sclauzero, EPFL SB ITP CSEA
   PH H2 462, Station 3, CH-1015 Lausanne

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[Pw_forum] spin-polarized results error

[Giuseppe Mattioli]

Dear Gao Min
Calculations of isolated atoms are tricky... Have a look at 
yourespresso/examples/example11
HTH

Giuseppe Mattioli

P.S. Do not forget your affiliation in further contributions...

On Thursday 13 January 2011 04:37:00 Fen Hong wrote:
> Dear all,
> I was trying to calculate Au atom with spin-polarized by norm-conserving
> scalar relativistic pseudopotential.
> The Au configuration is 5d106s1.
> I thought it would give the result 1, while what I got is "
>  total magnetization   = 0.00 Bohr mag/cell
>  absolute magnetization= 0.00 Bohr mag/cell
> "  Could anyone give me some tips about this or I misunderstand something.
> Thank you very much.
> the Input
> &CONTROL
>   calculation= "relax",
>   prefix = "Au-30"
>   nstep  = 500,
>   pseudo_dir   = "/home/Au",
>   outdir   = "/scr/",
> /
> &SYSTEM
>   ibrav  = 4,
>   celldm(1)  = 33.123112,
>   celldm(3)  = 1.42628937,
>   nat= 1,
>   ntyp   = 1,
>   ecutwfc= 30.0D0,
>   nspin  = 2,
>   starting_magnetization(1) = 0.2,
>   occupations  = "smearing",
>   degauss  = 0.05,
> /
> &ELECTRONS
>   conv_thr= 1.0D-8,
>   mixing_beta = 0.3D0,
>   electron_maxstep = 400,
> /
> &IONS
>   ds= 1.D-8,
> /
> ATOMIC_SPECIES
> Au 196.96655Au-wc.UPF
> ATOMIC_POSITIONS { angstrom }
> Au  3.755923000  7.951333000  7.475759000
> K_POINTS {gamma}
>
> Best wishes,
> Gao Min
> Japan



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[Pw_forum] spin polarized insulator

[S. K. S.]

Dear All,

In the recent version of QE code, is this possible to compute
the dielectric constant of a spin-polarized insulator ?

Thanking you and with my best regards,

Saha SK
JNCASR
Bangalore

[Pw_forum] Spin polarized calculation

[naz...@iasbs.ac.ir]

Dear All,
In Vasp there is two options
for doing spin polarized computations : ISPIN=2 which is done without any
restriction. And ISPIN=2 and NUPDOWAN=2 or 4. In the later casse? the spin
polarized caculation is done with imposing restriction on the number of
alpha and beta electrons. I wish two konw what are the equivalent
cases?for spin polarized calculation in ?PWSCF
?
Regards
Fariba Nazari
IASBS?

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[Pw_forum] Spin polarized calculation

[Duy Le]

There should be something called constrained_magnetization and
fixed_magnetization in the manual. I haven't used them so I have no
further comment.
--
Duy Le
PhD Student
Department of Physics
University of Central Florida.

"Men don't need hand to do things"



On Mon, Sep 6, 2010 at 5:02 AM,   wrote:
> Dear All,
>
> In Vasp there is two options for doing spin polarized computations : ISPIN=2
> which is done without any restriction. And ISPIN=2 and NUPDOWAN=2 or 4. In
> the later casse? the spin polarized caculation is done with imposing
> restriction on the number of alpha and beta electrons. I wish two konw what
> are the equivalent cases?for spin polarized calculation in ?PWSCF ?
>
> Regards
>
> Fariba Nazari
>
> IASBS
>
> --
> This message has been scanned for viruses and
> dangerous content by MailScanner, and is
> believed to be clean.
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
>
>

[Pw_forum] Spin polarized calculation

[Matteo Cococcioni]

Dear Fariba,

there is a number of options to constrain the magnetization (e.g., imposing
a specific multiplicity).
Please take a look to the Doc/INPUT_PW file of the distribution.

regards,

Matteo



On Mon, Sep 6, 2010 at 4:02 AM,  wrote:

> Dear All,
>
> In Vasp there is two options for doing spin polarized computations :
> ISPIN=2 which is done without any restriction. And ISPIN=2 and NUPDOWAN=2 or
> 4. In the later casse  the spin polarized caculation is done with imposing
> restriction on the number of alpha and beta electrons. I wish two konw what
> are the equivalent cases for spin polarized calculation in  PWSCF ?
>
> Regards
>
> Fariba Nazari
>
> IASBS
>
> --
> This message has been scanned for viruses and
> dangerous content by *MailScanner* , and is
> believed to be clean.
>
> ___
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/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
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[Pw_forum] spin multiplicity

[Weyl Fang]

  Dear all,

Recently i am working on a slab with the QE-4.1.2. I use the 
spin-polarized calculation through setting spin multiplicity. But i can 
not find the spin multiplicity in QE-4.2. Is this not provided in 
QE-4.2? If i want to set the spin multiplicity, how can i do it?

Any suggestions will be appreciated.
Thanks!

Weyl FANG

=
Weyl FANG
Graduate student in Chemical Engineering
State Key Laboratory of Materials-oriented Chemical Engineering
College of Chemistry and Chemical Engineering
Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
*
Email: weylfang at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing, 
Jiangsu, China
*

[Pw_forum] spin multiplicity

[Paolo Giannozzi]

On Jun 17, 2010, at 4:54 , Weyl Fang wrote:

>  i can not find the spin multiplicity in QE-4.2.

use "tot_magnetization"  - P.
---
Paolo Giannozzi, Dept of Physics, University of Udine
via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222

[Pw_forum] Spin polarized option for tetragonal

[Paolo Giannozzi]

On May 28, 2010, at 7:34 , Vi Vo wrote:

>nelec = 840

no longer present since v.4.2 (see Doc/release-notes)

> npsin = 2

npsin != nspin
---
Paolo Giannozzi, Dept of Physics, University of Udine
via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222

[Pw_forum] Spin polarized option for tetragonal

[Vi Vo]

Dear PWSCF users,

I set up an input to run a scf calculation for a body center tetragonal (BCT) 
system (ibrav=7), with nspin=2  (spin-polarized).  However, I kept having the 
following errors:

 task # 5
 from  read_namelists  : error #19
  reading namelist system

I am not sure if the spin polarized option is implemented for  BCT case or my 
input is wrong.  Could you help me with this.
  Below is a section of my input (I have error in the system namelist):

 &system
ibrav=  7
celldm(1) = 31.535747297405
celldm(3) = 1.3342521572387
nat=104, ntyp= 3
nbnd= 840
nelec = 840
npsin = 2
starting_magnetization(1)=0.7,
occupations='smearing', smearing='marzari-vanderbilt', degauss=0.008
ecutwfc = 30.0
 /
 &electrons
diagonalization='cg'
mixing_beta = 0.30
conv_thr =  1.0d-7
/
ATOMIC_SPECIES
 Sb 121.757   Sb.rel-pbe-rrkj.UPF
 Mn 54.93805 Mn.pbe-sp-van.UPF
 Ca 40.078Ca.pbe-nsp-van.UPF
ATOMIC_POSITIONS crystal
Sb  0.7500  0.5105  0.9895
Sb  0.7500  0.2395  0.2605
Sb  0.9790  0.2605  0.5105
...
Mn ...

  Thank you very much,

Vi Vo
Chemical Engineering,
University of Houston


  
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