Re: [QE-users] Dense k Point Interpolation to Arbitrary k Points for a Band Structure

[Lorenzo Paulatto]

> But I don't know how QE transforms the k vector corresponding to K and G to a 
> single number. I tried to read the source code but didn't understand it.
Hello,
it is just the length of the path. If you have two points, k and k', the length 
will be zero at the first point, and |k-k'| at the second, if you add a third 
point k'', then you also add a length |k'-k''| and so on. There are some 
special rules to detect equivalent points and changes of directions, but they 
do not matter here.

To make it even simpler, if you see that the crossing appear at i.e. 30% of the 
segment between k and k', you can just add a point k + 0.3(k'-k) = 0.7k + 0.3k'
hth
--
Lorenzo Paulatto - Paris
On Mar 23 2021, at 5:19 am, Truman Ng Yu  wrote:
>
> Hi Lorenzo,
>
> Thanks for your reply. I just set lsym=.false. and no_overlap=.false. and ran 
> bands.x again as you suggested. I'm waiting for the results now.
>
> Just in case it doesn't work, may I have more details on how to find out the 
> intersection points by hand? In the output of the original band structure 
> calculation, K is located at 0.000 and G at 0.750 along the horizontal axis. 
> But I don't know how QE transforms the k vector corresponding to K and G to a 
> single number. I tried to read the source code but didn't understand it.
>
> In the bands calculation, the specific k points are chosen unlike the scf 
> calculation where it's automatic. May I know how the grid is formed based on 
> the specific k points? Then, I'd be able to check that the intersection 
> points lie on the grid.
>
> Thanks.
>
> Regards,
> Truman
> National University of Singapore
> From: users  on behalf of Lorenzo 
> Paulatto 
> Sent: Tuesday, March 23, 2021 12:53 AM
> To: Quantum ESPRESSO users Forum 
> Subject: Re: [QE-users] Dense k Point Interpolation to Arbitrary k Points for 
> a Band Structure
>
>
>
> - External Email -
>
>
>
>
>
> Hello Truman,
> the bands code decides if bands cross or avoid using different criteria: per 
> default symmetry, otherwise overlap of wfcs. You may getting a better result 
> by changing criteria. Otherwise, you'll have to find the intersection point 
> by hand, but if it incommensurate with the grid, it will always show as a 
> discontinuity if you zoom in close enough
>
> regards
> --
> Lorenzo Paulatto - Paris
>
> On Mar 22 2021, at 4:27 pm, Truman Ng Yu  wrote:
> >
> > Hi QE users,
> >
> > I'm using QE 6.7MaX. I plotted a band structure with the following k point 
> > coordinates.
> >
> > K_POINTS {crystal_b}
> > 2
> > 0.375 0.375 0.750 2000 !K
> > 0.000 0.000 0.000 2000 !G
> >
> >
> > I'd like to include specific k points in between K and G such that the 
> > expected band crossing at the red dot in the figure below is captured in 
> > the band structure. How do I choose the k points such that this is possible?
> >
> >
> >
> > Thanks.
> >
> > Regards,
> > Truman
> > National University of Singapore
> > ___
> > Quantum ESPRESSO is supported by MaX 
> > (https://ddec1-0-en-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=www.max%2dcentre.eu&umid=61254bc7-7283-4c83-82cf-caf8de7ff73d&auth=8d3ccd473d52f326e51c0f75cb32c9541898e5d5-f0f4a8ee4cc782ae5521d01e88692d06d7daac84)
> > users mailing list users@lists.quantum-espresso.org
> > https://ddec1-0-en-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2flists.quantum%2despresso.org%2fmailman%2flistinfo%2fusers&umid=61254bc7-7283-4c83-82cf-caf8de7ff73d&auth=8d3ccd473d52f326e51c0f75cb32c9541898e5d5-867140e5c3e6b62f783eb9e91cb5fa75247edb38
>
>
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users

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

Re: [QE-users] Problem with ph.x

[Carlos Reis]

Dear Paolo

Thank you very much for your feedback.

Is there any tool that I can use to convert the unit cell vectors and
atomic positions in a format so that q-e recognize the correct symmetry and
generates the appropriate input for q-e?

Best regards,
Carlos Reis.


On Mon, Mar 22, 2021 at 8:50 PM Paolo Giannozzi 
wrote:

> Well, no, it's the same problem that was reported some time ago. Your
> lattice has a higher symmetry (tetragonal I) than triclinic (ibrav=14):
>ibrav = 7, celldm(1) = 16.22739617, celldm(3) =  0.6324556
> corresponding to crystal axes (alat units)
>a(1) = (   0.50  -0.50   0.316228 )
>a(2) = (   0.50   0.50   0.316228 )
>a(3) = (  -0.50  -0.50   0.316228 )
> with atomic positions (no warranty):
> ATOMIC_POSITIONS {alat}
>  Si  0.000   0.000   0.000
>  Si  0.400   0.800   0.000
>  Si  0.600   0.200   0.000
>  Si  0.200   0.400   0.000
>  Si  1.000   0.500   0.1581139
>  Si  0.600   0.700   0.1581139
>  Si  0.400   0.300   0.1581139
>  Si  0.200  -0.100   0.1581139
>  C   0.800   0.600   0.000
>  C   0.800   0.100   0.1581139
>
> The symmetry searching algorithm detects one symmetry, in addition to the
> identity, and this is compatible with the FFT grid computed for the
> tetragonal I lattice (48 48 48: the three lattice vectors have the same
> length), but not for the triclinic lattice (60 60 48: two vectors have the
> same length, different from the third).
>
> Paolo
>
> On Mon, Mar 22, 2021 at 9:35 AM Paolo Giannozzi 
> wrote:
>
>> Very strange. I have opened an item in the "Issues" section:
>>https://gitlab.com/QEF/q-e/-/issues/301
>> Paolo
>>
>> On Tue, Mar 16, 2021 at 7:26 PM Carlos Reis 
>> wrote:
>>
>>> Hello
>>>
>>> I use this file to perform a scf calculation
>>>
>>> &CONTROL
>>>   calculation = 'scf',
>>>pseudo_dir = '.',
>>>wf_collect = .true.,
>>> /
>>> &SYSTEM
>>>   ibrav = 14,
>>>  celldm(1) = 16.22739617
>>>  celldm(2) =  1.
>>>  celldm(3) =  0.77459667
>>>  celldm(4) =  0.64549723
>>>  celldm(5) =  0.64549723
>>> nat =10 ,
>>>ntyp = 2 ,
>>>nbnd =28 ,
>>> ecutwfc = 30.000 ,
>>> /
>>> &ELECTRONS
>>>   diagonalization = 'david',
>>> /
>>> ATOMIC_SPECIES
>>> Si28.085500   Si.UPF
>>> C 12.011000C.UPF
>>> ATOMIC_POSITIONS {crystal}
>>>Si  -0. -0.  0.
>>>Si   0.4000  0.8000  0.
>>>Si   0.6000  0.2000  0.
>>>Si   0.2000  0.4000  0.
>>>Si   0.7500  0.2500  0.5000
>>>Si   0.3500  0.4500  0.5000
>>>Si   0.1500  0.0500  0.5000
>>>Si  -0.0500 -0.3500  0.5000
>>>C0.8000  0.6000  0.
>>>C0.5500 -0.1500  0.5000
>>> K_POINTS {automatic}
>>>4   4   4   1   1   1
>>>
>>> and then I run ph.x with this input file:
>>>
>>> --
>>> &inputph
>>>   prefix   = 'pwscf',
>>>   epsil= .false.,
>>>   fildyn   = 'pwscf.dyn',
>>>   ldisp= .true.
>>>   fildvscf = 'dvscf'
>>>   nq1=1,
>>>   nq2=1,
>>>   nq3=1,
>>>  /
>>>
>>> Program PHONON v.6.7MaX starts on 16Mar2021 at 17:18:57
>>>
>>>  This program is part of the open-source Quantum ESPRESSO suite
>>>  for quantum simulation of materials; please cite
>>>  "P. Giannozzi et al., J. Phys.:Condens. Matter 21 395502 (2009);
>>>  "P. Giannozzi et al., J. Phys.:Condens. Matter 29 465901 (2017);
>>>   URL http://www.quantum-espresso.org";,
>>>  in publications or presentations arising from this work. More
>>> details at
>>>  http://www.quantum-espresso.org/quote
>>>
>>>  Parallel version (MPI), running on16 processors
>>>
>>>  MPI processes distributed on 1 nodes
>>>  K-points division: npool =  16
>>>  Waiting for input...
>>>  Reading input from standard input
>>>
>>>  Reading xml data from directory:
>>>
>>>  ./pwscf.save/
>>>  file C.UPF: wavefunction(s)  3d renormalized
>>>
>>>  IMPORTANT: XC functional enforced from input :
>>>  Exchange-correlation= PZ
>>>(   1   1   0   0   0   0   0)
>>>  Any further DFT definition will be discarded
>>>  Please, verify this is what you really want
>>>
>>>
>>>  G-vector sticks info
>>>  
>>>  sticks:   dense  smooth PW G-vecs:dense   smooth  PW
>>>  Sum2521252182130009300095631
>>>
>>>  Reading co

[QE-users] Simulated STM

[HUSSAM BOUAAMLAT]

Dear QE users,

I am trying to simulate STM images, the only problem I have is the bias
voltage.
in experimental we use, for example, V = 0.3 V, but when I use QE I have to
use atomic units. So what is the value I need to get the same V = 0.3V
value? I'm sorry if this question sounds trivial.

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

Re: [QE-users] Simulated STM

[Giuseppe Mattioli]

Dear Hussam Bouaamlat (please sign always your posts to the forum with  
name and scientific affiliation)
The negative or positive external potential applied to the STM tip  
roughly corresponds (if you neglect charging effects depending also on  
the tunneling current) to the offset between the Fermi level of your  
system and the maximum/minimum potential of the injected/extracted  
electron in the simulated STM. For one electron, the potential bias  
(in V) corresponds to a given energy offset (in eV), that you can  
easily convert to the value in Rydberg a.u. (1 Ry = 13.606 eV).

HTH
Giuseppe

Quoting HUSSAM BOUAAMLAT :


Dear QE users,

I am trying to simulate STM images, the only problem I have is the bias
voltage.
in experimental we use, for example, V = 0.3 V, but when I use QE I have to
use atomic units. So what is the value I need to get the same V = 0.3V
value? I'm sorry if this question sounds trivial.

Best regards,




GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: 

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

Re: [QE-users] Problem with ph.x

[Offermans Willem]

Dear Carlos and Quantum Espresso friends,

In the past, I had severe problems with symmetry detection by Quantum Espresso.
I’m studying stepped surfaces, such as Pt(221) and Pt(533) with S_2 symmetry.
Depending on how I define the unit cell and the positions of the slab atoms 
therein,
QE could or could not detect right symmetry.

Someone pointed out to use gener_3d_slab tool from thermo_pw to generate
the structures. Indeed, the structures generated by gener_3d_slab are better
handled by QE with respect to symmetry detection, but it is not 100% user proof.
Even now, I have systems where I start with relaxing a structure with S2 
symmetry, 
but loosing the symmetry upon restarts of the calculations. In the latter case, 
I need
to redefine the positions of the slab atoms to regenerate the right symmetry.

B.t.w. thermo_pw is located here:

https://github.com/dalcorso/thermo_pw 




Met vriendelijke groeten,
Mit freundlichen Grüßen,
With kind regards,


Willem Offermans
Researcher Electrocatalysis SCT
VITO NV | Boeretang 200 | 2400 Mol
Phone:+32(0)14335263 Mobile:+32(0)492182073 

willem.offerm...@vito.be



> On 23 Mar 2021, at 10:45, Carlos Reis  wrote:
> 
> Dear Paolo
> 
> Thank you very much for your feedback.
> 
> Is there any tool that I can use to convert the unit cell vectors and atomic 
> positions in a format so that q-e recognize the correct symmetry and 
> generates the appropriate input for q-e?
> 
> Best regards,
> Carlos Reis.
> 
> 
> On Mon, Mar 22, 2021 at 8:50 PM Paolo Giannozzi  > wrote:
> Well, no, it's the same problem that was reported some time ago. Your lattice 
> has a higher symmetry (tetragonal I) than triclinic (ibrav=14):
>ibrav = 7, celldm(1) = 16.22739617, celldm(3) =  0.6324556
> corresponding to crystal axes (alat units)
>a(1) = (   0.50  -0.50   0.316228 )
>a(2) = (   0.50   0.50   0.316228 )
>a(3) = (  -0.50  -0.50   0.316228 )
> with atomic positions (no warranty):
> ATOMIC_POSITIONS {alat}
>  Si  0.000   0.000   0.000
>  Si  0.400   0.800   0.000
>  Si  0.600   0.200   0.000
>  Si  0.200   0.400   0.000
>  Si  1.000   0.500   0.1581139
>  Si  0.600   0.700   0.1581139
>  Si  0.400   0.300   0.1581139
>  Si  0.200  -0.100   0.1581139
>  C   0.800   0.600   0.000
>  C   0.800   0.100   0.1581139
> 
> The symmetry searching algorithm detects one symmetry, in addition to the 
> identity, and this is compatible with the FFT grid computed for the 
> tetragonal I lattice (48 48 48: the three lattice vectors have the same 
> length), but not for the triclinic lattice (60 60 48: two vectors have the 
> same length, different from the third).
> 
> Paolo
> 
> On Mon, Mar 22, 2021 at 9:35 AM Paolo Giannozzi  > wrote:
> Very strange. I have opened an item in the "Issues" section:
>https://gitlab.com/QEF/q-e/-/issues/301 
> 
> Paolo
> 
> On Tue, Mar 16, 2021 at 7:26 PM Carlos Reis  > wrote:
> Hello
> 
> I use this file to perform a scf calculation
> 
> &CONTROL
>   calculation = 'scf',
>pseudo_dir = '.',
>wf_collect = .true.,
> /
> &SYSTEM
>   ibrav = 14,
>  celldm(1) = 16.22739617
>  celldm(2) =  1.
>  celldm(3) =  0.77459667
>  celldm(4) =  0.64549723
>  celldm(5) =  0.64549723
> nat =10 ,
>ntyp = 2 ,
>nbnd =28 ,
> ecutwfc = 30.000 ,
> /
> &ELECTRONS
>   diagonalization = 'david',
> /
> ATOMIC_SPECIES
> Si28.085500   Si.UPF
> C 12.011000C.UPF
> ATOMIC_POSITIONS {crystal}
>Si  -0. -0.  0.
>Si   0.4000  0.8000  0.
>Si   0.6000  0.2000  0.
>Si   0.2000  0.4000  0.
>Si   0.7500  0.2500  0.5000
>Si   0.3500  0.4500  0.5000
>Si   0.1500  0.0500  0.5000
>Si  -0.0500 -0.3500  0.5000
>C0.8000  0.6000  0.
>C0.5500 -0.1500  0.5000
> K_POINTS {automatic}
>4   4   4   1   1   1
> 
> and then I run ph.x with this input file:
> 
> --
> 

[QE-users] Symmetry detection by pw.x

[Offermans Willem]

Dear Quantum Espresso friends,

Hereafter you will find two pw.x input files: InputFile A and InputFile B.
The files define the same system.
The only difference is that in one of the files the atomic positions are 
translated
to positions within the unit cell and to positions in the middle of the unit 
cell.

Thereafter you will find snippets from the corresponding output files: 
OutputFile A
and OutputFile B. The snippets show the detected symmetry by the  __same__ 
executable, namely:
Program PWSCF v.6.3 starts on 23Mar2021 at 13:26:13 for A.
Program PWSCF v.6.3 starts on 23Mar2021 at 17:37:55 for B

Case A detects S_2 symmetry
Case B detects no symmetry

So translation of the structure within unit-cell changes the detected symmetry.

Is there something I could do to seduce pw.x to find the S_2 symmetry in case B 
as well,
besides transforming structure B back to A. 

If not, how can I translate the calculated “ionic+hartree potential” in the 
same way, I have
translated A to B?  


InputFileA:


&CONTROL
   verbosity= 'high'
   tprnfor  = .true.
   forc_conv_thr= 1e-09
   pseudo_dir   = 
'/scratch/antwerpen/205/vsc20500/q-e/Pt/Pt_surface_GGA_PBE_PAW/Pt221/5M3V2x1/'
/
&SYSTEM
   ecutwfc  = 35
   ecutrho  = 560
   occupations  = 'smearing'
   degauss  = 1e-05
   ntyp = 1
   nat  = 38
   ibrav= 0
/
&ELECTRONS
   electron_maxstep = 200
   conv_thr = 1e-09
   mixing_beta  = 0.3
   startingpot  = 'atomic'
   startingwfc  = 'atomic+random'
/
&IONS
/
&CELL
/

ATOMIC_SPECIES
Pt 195.084 Pt.pbe-n-kjpaw_psl.1.0.0.UPF

K_POINTS automatic
6 9 1  0 0 0

CELL_PARAMETERS angstrom
5.624032 0.00 0.00
0.00 8.436048 0.00
0.00 0.00 21.20955287898742

ATOMIC_POSITIONS angstrom
Pt 1.4061651002 4.0599411310 -5.7765621345 
Pt 0.0001532941 1.7985387032 -5.2526504899 
Pt 4.2182087563 -0.4283346742 -4.7009783468 
Pt 0.0001642593 -2.6944921967 -4.1391134796 
Pt 1.4061214817 3.3208797727 -3.2112557851 
Pt 0.915723 0.9297515096 -2.5916767224 
Pt 4.2180697756 -1.4119961580 -2.0256141024 
Pt 0.0001681387 -3.6890216255 -1.3344432894 
Pt 1.4059482538 2.3757383517 -0.6457302061 
Pt 0.214244 0.043088 0.001310 
Pt 4.2180785861 -2.3757701390 0.6456919793 
Pt -0.0001254110 3.6890210622 1.331299 
Pt 1.4059592199 1.4120176059 2.0255905238 
Pt -0.516748 -0.9297449833 2.5916824674 
Pt 4.2179139971 -3.3208839102 3.2112850131 
Pt -0.0001088908 2.6944929715 4.1391339215 
Pt 1.4058199721 0.4283047406 4.7009005036 
Pt -0.0001689240 -1.7985466686 5.2526278998 
Pt 4.2178754128 -4.0599850729 5.7766502906 
Pt -1.4058643961 4.0599845309 -5.7766494636 
Pt 2.8121853437 1.7985474679 -5.2526244777 
Pt 1.4061986231 -0.4283048223 -4.7009008877 
Pt 2.8121251844 -2.6944951419 -4.1391305996 
Pt -1.4059029525 3.3208833141 -3.2112851898 
Pt 2.8120672554 0.9297446276 -2.5916778170 
Pt 1.4060647774 -1.4120175477 -2.0255903657 
Pt 2.8121415804 -3.6890202774 -1.3344404060 
Pt -1.4060678415 2.3757703137 -0.6456913229 
Pt 2.8119945756 -0.043088 -0.001310 
Pt 1.4060730016 -2.3757385264 0.6457295497 
Pt 2.8118476919 3.6890208407 1.3344395655 
Pt -1.4060617729 1.4119960999 2.0256139443 
Pt 2.8119248472 -0.9297511539 2.5916720720 
Pt 1.4058994737 -3.3208791766 3.2112559618 
Pt 2.8118514471 2.6944943671 4.1391101577 
Pt -1.4061953515 0.4283347559 4.7009787310 
Pt 2.8118622861 -1.7985395025 5.2526470679 
Pt 1.4058558831 -4.0599405891 5.7765613074 


InputFile B:


&CONTROL
   verbosity= 'high'
   tprnfor  = .true.
   forc_conv_thr= 1e-09
   pseudo_dir   = './'
/
&SYSTEM
   ecutwfc  = 35
   ecutrho  = 560
   occupations  = 'smearing'
   degauss  = 1e-05
   ntyp = 1
   nat  = 38
   ibrav= 0
/
&ELECTRONS
   electron_maxstep = 200
   conv_thr = 1e-09
   mixing_beta  = 0.3
   startingpot  = 'atomic'
   startingwfc  = 'atomic+random'
/
&IONS
/
&CELL
/

ATOMIC_SPECIES
Pt 195.084 Pt.pbe-n-kjpaw_psl.1.0.0.UPF

K_POINTS automatic
6 9 1  0 0 0

CELL_PARAMETERS angstrom
5.624032 0.00 0.00
0.00 8.436048 0.00
0.00 0.00 21.20955287898742

ATOMIC_POSITIONS angstrom
Pt 1.4061436758 4.0599368223 4.8282141739 
Pt 0.0001318697 1.7985343944 5.3521258185 
Pt 4.2181873319 8.0077090170 5.9037979616 
Pt 0.0001428348 5.7415514945 6.4656628288 
Pt 1.4061000572 3.3208754639 7.3935205233 
Pt 0.701479 0.9297472008 8.0130995860 
Pt 4.2180483511 7.0240475332 8.5791622060 
Pt 0.0001467143 4.7470220657 9.2703330190 
Pt 1.4059268293 2.3757340429 9.9590461024 
Pt 0.00 0.00 10.6047764395 
Pt 4.2180571617 6.0602735522 11.2504682877 
Pt 5.6238851646 3.6890167534 11.9392204383 
Pt 1.4059377955 1.4120132971 12.6303668322 
Pt 5.6239589008 7.5062987079 13.1964587759 
Pt 4.2178925726 5.1

Re: [QE-users] Problem with ph.x

[Carlos Reis]

Dear Willem

Thank you very much for your suggestion of themo_pw.

This package has a nice feature that does exactly what I want.

I ran thermo_pw with this control file

&INPUT_THERMO
 find_ibrav=.TRUE.
  what='scf',
 /

using a pw.x input file with ibrav=0 , unit cell vectors and atomic
positions referred to original vectors
(which is what I have) the program outputs the correct ibrav, celldm, and
atomic positions referred to allat.

so apparently it solves my problem!

described here

https://people.sissa.it/~dalcorso/thermo_pw/tutorial/node4.html

Best regards,
Carlos Reis.



On Tue, Mar 23, 2021 at 11:00 AM Offermans Willem 
wrote:

> Dear Carlos and Quantum Espresso friends,
>
> In the past, I had severe problems with symmetry detection by Quantum
> Espresso.
> I’m studying stepped surfaces, such as Pt(221) and Pt(533) with S_2
> symmetry.
> Depending on how I define the unit cell and the positions of the slab
> atoms therein,
> QE could or could not detect right symmetry.
>
> Someone pointed out to use gener_3d_slab tool from thermo_pw to generate
> the structures. Indeed, the structures generated by gener_3d_slab are
> better
> handled by QE with respect to symmetry detection, but it is not 100% user
> proof.
> Even now, I have systems where I start with relaxing a structure with S2
> symmetry,
> but loosing the symmetry upon restarts of the calculations. In the latter
> case, I need
> to redefine the positions of the slab atoms to regenerate the right
> symmetry.
>
> B.t.w. thermo_pw is located here:
>
> https://github.com/dalcorso/thermo_pw
>
>
>
>
> Met vriendelijke groeten,
> Mit freundlichen Grüßen,
> With kind regards,
>
>
> Willem Offermans
> Researcher Electrocatalysis SCT
> VITO NV | Boeretang 200 | 2400 Mol
> Phone:+32(0)14335263 Mobile:+32(0)492182073
>
> willem.offerm...@vito.be
>
>
> On 23 Mar 2021, at 10:45, Carlos Reis  wrote:
>
> Dear Paolo
>
> Thank you very much for your feedback.
>
> Is there any tool that I can use to convert the unit cell vectors and
> atomic positions in a format so that q-e recognize the correct symmetry and
> generates the appropriate input for q-e?
>
> Best regards,
> Carlos Reis.
>
>
> On Mon, Mar 22, 2021 at 8:50 PM Paolo Giannozzi 
> wrote:
>
>> Well, no, it's the same problem that was reported some time ago. Your
>> lattice has a higher symmetry (tetragonal I) than triclinic (ibrav=14):
>>ibrav = 7, celldm(1) = 16.22739617, celldm(3) =  0.6324556
>> corresponding to crystal axes (alat units)
>>a(1) = (   0.50  -0.50   0.316228 )
>>a(2) = (   0.50   0.50   0.316228 )
>>a(3) = (  -0.50  -0.50   0.316228 )
>> with atomic positions (no warranty):
>> ATOMIC_POSITIONS {alat}
>>  Si  0.000   0.000   0.000
>>  Si  0.400   0.800   0.000
>>  Si  0.600   0.200   0.000
>>  Si  0.200   0.400   0.000
>>  Si  1.000   0.500   0.1581139
>>  Si  0.600   0.700   0.1581139
>>  Si  0.400   0.300   0.1581139
>>  Si  0.200  -0.100   0.1581139
>>  C   0.800   0.600   0.000
>>  C   0.800   0.100   0.1581139
>>
>> The symmetry searching algorithm detects one symmetry, in addition to the
>> identity, and this is compatible with the FFT grid computed for the
>> tetragonal I lattice (48 48 48: the three lattice vectors have the same
>> length), but not for the triclinic lattice (60 60 48: two vectors have the
>> same length, different from the third).
>>
>> Paolo
>>
>> On Mon, Mar 22, 2021 at 9:35 AM Paolo Giannozzi 
>> wrote:
>>
>>> Very strange. I have opened an item in the "Issues" section:
>>>https://gitlab.com/QEF/q-e/-/issues/301
>>> 
>>> Paolo
>>>
>>> On Tue, Mar 16, 2021 at 7:26 PM Carlos Reis 
>>> wrote:
>>>
 Hello

 I use this file to perform a scf calculation

 &CONTROL
   calculation = 'scf',
pseudo_dir = '.',
wf_collect = .true.,
 /
 &SYSTEM
   ibrav = 14,
  celldm(1) = 16.22739617
  celldm(2) =  1.
  celldm(3) =  0.77459667
  celldm(4) =  0.64549723
  celldm(5) =  0.64549723
 nat =10 ,
ntyp = 2 ,
nbnd =28 ,
 ecutwfc = 30.000 ,
 /
 &ELECTRONS
   diagonalization = 'david',
 /
 ATOMIC_SPECIES
 Si28.085500   Si.UPF
 C 12.011000C.UPF
 ATOMIC_POSITIONS {crystal}

[QE-users] [QE-developers] Free electron wavefunctions

[Qinxue Cao]

Dear QE Community and DevelopersMy colleagues and I are currently trying to
find a way to output 'free electron wavefunctions' from QE. More
specifically, we wish to simulate a 1D array of silicon atoms. We were
thinking to do this by deleting the cell-dependent part of the Bloch
wavefunctions in the directions transverse to the length of the 1D array
keeping only the kpoint-dependent e^ikx term in those directions. What
would be a reasonable way to accomplish this in QE? We are totally fine
with modifying the code. Our end goal is to have the modified wavefunctions
in the same format as QE normally writes production wavefunctions to files.
Best,
Qinxue Cao
Department of Electrical and Computer Engineering
Boston University
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users

Re: [QE-users] pp.x calculation very slow

[Lenz Fiedler]

Dear Professor Giannozzi,

So if I understand you correctly, you did something like

mpirun -np 18 pp.x -in Fe.pp.ldos.in

on the nscf data wirh 14x14x14 and got the 560 cube files in 30 minutes?
This is what I would expect/hope for as well. I will try this and if I
cannot reproduce it there might be something wrong with my installation.

Kind regards
Lenz


Am So., 21. März 2021 um 16:31 Uhr schrieb Paolo Giannozzi <
p.gianno...@gmail.com>:

> A LDOS calculation should take more or less the same time as the
> calculation of the charge density, plus reading, wroting, etc.. I just
> tried and it took half an hour on 18 processors (CPU cores, not GPUs)
>
> Paolo
>
> On Wed, Mar 17, 2021 at 5:26 PM Lenz Fiedler 
> wrote:
>
>> Dear Professor Giannozzi,
>>
>> Thank you so much for your answer. You are right, I did not really think
>> about the parallelization for the initial SCF calculation, I was more
>> puzzled by the pp.x calculation. If I understand you correctly, using
>> something like "pp.x -nk 16" might also help speed up the LDOS calculation
>> as well? But there also might be an upper limit of how fast this performs
>> and it could be that I simply have to wait a while to obtain the LDOS? As
>> in, except for my suboptimal parallelization strategy, the long runtime of
>> pp.x I observed was not due to wrong usage but simply to computational load
>> of the problem?
>>
>> Kind regards
>> Lenz Fiedler
>>
>> PhD Student (HZDR / CASUS)
>>
>>
>> Am Di., 16. März 2021 um 16:36 Uhr schrieb Paolo Giannozzi <
>> p.gianno...@gmail.com>:
>>
>>> Your supercell is small but you have a high cutoff and a large number of
>>> k-points, which makes the overall computational load quite heavy. Moreover
>>> your choice of parallelization is less than optimal: you should use both
>>> k-point and plane-wave parallelization, something like "mpirun -np 160 pw.x
>>> -nk 16" or so. For reference: I ran your Fe.pw.scf.in input in 20' on a
>>> small 36-core machine with two (powerful) GPU's. The nscf calculation took
>>> 1h20' for the calculation and is taking as much time if not more to write
>>> the files. Also note that not all postprocessing calculations are optimized
>>> for large runs.
>>>
>>> Paolo
>>>
>>> On Mon, Mar 15, 2021 at 7:23 PM Lenz Fiedler 
>>> wrote:
>>>
 (resent because something went wrong with the header line)

 Hi users,

 I am experiencing a problem with pp.x. I want to calculate the LDOS for
 a 16 Fe atom supercell using a 560 value energy grid and the 3D grid given
 by the DFT calculation (100x100x100 grid points). I have performed the DFT
 calculation by first doing a SCF calculation (8x8x8 k-points) and then a
 non-SCF calculation (14x14x14 k-points) successfully. Now I am trying to
 do:

 mpirun -np 160 pp.x -in Fe.pp.ldos.in

 but the calculation takes way longer than I anticipated. The entire DFT
 calculation took less than a day, while for the LDOS, after about 12 hours,
 only 20 tmp files had been written. Am I doing something wrong? Or is this
 expected? At this rate, calculating the LDOS would take days, which is why
 I am assuming I am doing something wrong.
 Please find my output and input files here:


 https://drive.google.com/drive/folders/1R-m5jlw1bcNxe3nBXjc4dms-IoMMp4Ir?usp=sharing
 (the pp.out file is from a run where I investigated if a lower number
 of CPUs helps, but that was slower, as expected.)

 Kind regards
 Lenz

 PhD Student (HZDR / CASUS)
 ___
 Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
 users mailing list users@lists.quantum-espresso.org
 https://lists.quantum-espresso.org/mailman/listinfo/users
>>>
>>>
>>>
>>> --
>>> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
>>> Univ. Udine, via delle Scienze 206, 33100 Udine, Italy
>>> Phone +39-0432-558216, fax +39-0432-558222
>>>
>>> ___
>>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>>> users mailing list users@lists.quantum-espresso.org
>>> https://lists.quantum-espresso.org/mailman/listinfo/users
>>
>> ___
>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>> users mailing list users@lists.quantum-espresso.org
>> https://lists.quantum-espresso.org/mailman/listinfo/users
>
>
>
> --
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 206, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222
>
> ___
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users@lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espress

[QE-users] 0.0000 in QHA outputs

[Dr. K. C. Bhamu]

Dear Quantum Espresso/QHA Users
I am trying to calculate the entropy of a molecule (49atoms, C and H) in
the gas phase using QHA provided with QE6.6.
I could run the examples supplied with the QHA code.
But when I run it for H2 molecule, I always get 0. in the
case(H2).QHA.out file.
Similar information (0.000) is written in other files also.

What could be wrong?
I have edited the Edit_Me file properly.
Few header rows from H2.QHA.out file is mentioned below while the entire
directory can be downloaded from here .

# Zero vibration energy:  0.00  (Ry/cell)
# Phonon DOS norm  :  0.00  ! 3N for check purpose, N
number of atoms in the unit cell
# T in K, F_vib in Ry/cell, C_v in R (the universal gas constant by 3N
modes), S in k_B
#
#   T E_internalF_vibration  Specific heat (C_v)
Entropy

5.00  0.00  0.00   0.00
 0.00  *>> I used step 0.75 too*
   10.00  0.00  0.00   0.00
 0.00
   15.00  0.00  0.00   0.00
 0.00
   20.00  0.00  0.00   0.00
 0.00

Any help would be appreciated.

Regards

KC Bhamu(Ph.D.)
University of Ulsan
South Korea
___
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list users@lists.quantum-espresso.org
https://lists.quantum-espresso.org/mailman/listinfo/users