BSE spectra considering momentum

You can find here problems arising when using old releases of Yambo (< 5.0). Issues as parallelization strategy, performance issues and other technical aspects.

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Fadil
Posts: 56
Joined: Sun May 24, 2020 1:56 pm

Re: BSE spectra considering momentum

Post by Fadil » Wed May 18, 2022 9:49 am

Sorry I forgot to attach files.
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Dr. Fadıl İYİKANAT
ICFO-The Institute of Photonic Sciences
Barcelona-SPAIN

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Daniele Varsano
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Re: BSE spectra considering momentum

Post by Daniele Varsano » Wed May 18, 2022 12:12 pm

Dear Fadil,

check in your version the lines in K_output_file.F:
it should be:

Code: Select all

384  ! POLARIZABILITY
385  !----------------
386  !
387  if (eval_alpha_loc) then
388    !
389    if(l_col_cut.or.trim(alpha_dim)=="volume") then
390      alpha_factor=eps_2_alpha/4._SP/pi*bare_qpg(iq,1)**2/q_norm(iq)**2
391      alpha(:,1)=Epsilon_ii(:,2)*alpha_factor
392      alpha(:,2)=Epsilon_ii(:,3)*alpha_factor
393      if (l_print_col4) alpha(:,3)=Epsilon_ii(:,4)*alpha_factor
394    else
395      alpha_factor=eps_2_alpha/4._SP/pi
396      alpha=(1._SP+eels)*alpha_factor
397    endif
398    !
Here the problem of the q=0 has been fixed.
I think that the q=0 and q different from zero may have very different strengths, but what you get is quite unusual.

Best,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/

Fadil
Posts: 56
Joined: Sun May 24, 2020 1:56 pm

Re: BSE spectra considering momentum

Post by Fadil » Wed May 18, 2022 1:16 pm

Here, what I found for 5.0.3 and 5.0.4;
! POLARIZABILITY
!----------------
!
if (eval_alpha_loc) then
!
if(l_col_cut.or.trim(alpha_dim)=="volume") then
alpha_factor=eps_2_alpha/4._SP/pi*bare_qpg(1,1)**2/q_norm(1)**2
alpha(:,1)=Epsilon_ii(:,2)*alpha_factor
alpha(:,2)=Epsilon_ii(:,3)*alpha_factor
if (l_print_col4) alpha(:,3)=Epsilon_ii(:,4)*alpha_factor
else
alpha_factor=eps_2_alpha/4._SP/pi
alpha=(1._SP+eels)*alpha_factor
endif
I think problem in bare_qpg(1,1) and q_norm(1).
We need to change them as bare_qpg(iq,1) and q_norm(iq).
Dr. Fadıl İYİKANAT
ICFO-The Institute of Photonic Sciences
Barcelona-SPAIN

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Daniele Varsano
Posts: 3773
Joined: Tue Mar 17, 2009 2:23 pm
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Re: BSE spectra considering momentum

Post by Daniele Varsano » Wed May 18, 2022 1:42 pm

Dear Fadil,

yes, indeed this is the problem that was fixed.
Please note that yambo 5.1 has been just released.

Best,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/

Fadil
Posts: 56
Joined: Sun May 24, 2020 1:56 pm

Re: BSE spectra considering momentum

Post by Fadil » Wed May 18, 2022 4:27 pm

Yes, I noticed Yambo 5.1.
But I am having some installation problems on our cluster with 5.1.
Thank you!
Dr. Fadıl İYİKANAT
ICFO-The Institute of Photonic Sciences
Barcelona-SPAIN

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