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El-ph calculation on spin-polarized (LSDA) system

PostPosted: Tue Oct 03, 2017 7:20 am
by faozan
Dear Yambo Developer and Yambo users,

I have a problem in calculating electron-phonon coupling on spin-polarized material/LSDA (nspin = 2). Scf, nscf and ph.x calculation on the system are finished well, I faced difficulties in running ypp_ph (generating gkkp files), there is always an error message "PW(ELPH) databases ...[PHONON] ...incorrect K-point correspondance" , I have followed Dr. Alejandro's suggestion viewtopic.php?f=12&t=870 to change decimal precision on Kpoint, but the same problem still arose.
However, if I use non-polarized approach (nspin = 1), everything running well; unfortunately I got the wrong electronic structure.

Could you please to give me any suggestion how to perform electron-phonon calculation on the top of LSDA?
thank you

Best regards,
Faozan

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Tue Oct 03, 2017 8:24 am
by amolina
Dear Faozan,
can you upload your scf, nscf and input files for the phonons. In principle, pw and yambo work for spin-polarized materials. Which version of pw are you using?
Best,
Alejandro

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Tue Oct 03, 2017 8:57 am
by faozan
Dear Dr. Alejandro,

Thank you for your prompt reply, Please find my attached input-file.
I am using QE-6.1 and yambo-4.1.4

Best regards,
Faozan

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Wed Oct 04, 2017 3:27 pm
by amolina
Dear Faozan,
your script seems OK for me. Maybe you can try to use a uniform grid as this one:

DVSCF input
&inputph
nq2 = 6
nq3 = 6
nq1 = 6
fildvscf = 'dvscf'
search_sym = .false.
qplot = .false.
fildyn = 'ferh.dyn'
iverbosity = 1
ldisp = .true.
alpha_mix(1) = 0.4
tr2_ph = 5e-11
prefix = 'ferh'
electron_phonon = 'dvscf'
trans = .true.
last_q = 10
start_q = 10
/
ELPH input file:
&inputph
nq2 = 6
nq3 = 6
nq1 = 6
fildvscf = 'dvscf'
search_sym = .false.
qplot = .false.
fildyn = 'ferh.dyn'
iverbosity = 1
ldisp = .true.
alpha_mix(1) = 0.4
tr2_ph = 5e-11
prefix = 'ferh'
electron_phonon = 'yambo'
trans = .false.
last_q = 10
start_q = 10
/

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Thu Oct 05, 2017 12:35 am
by faozan
Dear Dr. Alejandro,
Thank you so much for checking my script, I'll try the input-file you suggest soon.

Best regards,
faozan

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Fri Oct 06, 2017 1:11 am
by faozan
Dear Dr. Alejandro,
I have tried your suggested input, but still I got the same error. Here attached the input and output file.

Best regards,
Faozan

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Thu Oct 19, 2017 8:19 am
by amolina
Dear Faozan,
can you upload the scf and nscf files, together with the pseudos? I will try to reproduce the error.
Alejandro.

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Sat Oct 21, 2017 11:40 pm
by faozan
Dear Dr. Alejandro,
Sorry for my delayed reply, I just read your post. Please find the attached files and thank you for your help.
regards,
Faozan

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Mon Oct 23, 2017 9:30 am
by amolina
Hi Faozan,
have you tried without the flag search_sym = .false.?
Cheers,
Alejandro.

Re: El-ph calculation on spin-polarized (LSDA) system

PostPosted: Mon Oct 23, 2017 11:13 pm
by faozan
Hi Dr. Alejandro,
Yes, I have tried without the flag, but with random kpoint and still failed. do you successfully reproduce the same error?

Best,
Faozan