Yambo Community Forum

Dear friends,

To do a BSE calculation, one can input the GW results either using the approximate scissor-and-stretching method (with "KfnQP_E") or directly importing the original results db.QP (with "KfnQPdb"). Sometimes, the GW corrections are complex and using db.QP is the only good choice.

The problem is that if I do the GW calculation in Abinit, how can I transform the Abinit results to the binary db.QP? What I hope to know is the file structure of db.QP. Can you enlighten me?

Sincerely,

PS. If KfnQPdb can also accept ASCII file, that whould be great.

Dear Guangfu Luo

it is not possible to import directly the ABINIT results in Yambo.

But as fas as I know other people modified yambo in order to do it.

Try to contact Silvana Botti

http://www.tddft.org/bmg/people.php?oid=5040305

Sincerely
Claudio Attaccalite

Dear Claudio,

Thanks very much for your infomation. I will contact Silvana Botti.

Sincerely,

Dear Guangfu Luo

in the last version of yambo 3,2,4,

http://www.yambo-code.org/download.php

we added a tool to write quasi-particle correction in the yambo database, ypp -q

regards
Claudio Attaccalite

Dear Claudio,

This is good news and thanks for your work. I execute "ypp -q" but found some part unclear for me. Specifically, I have two questions: (1) what is meaning of "Img(E)"? (2) Can I use more than one line to specify the QP correction one state by one state?

---------------parameters generated by "ypp -q"---------------------

qpdb # [R] Quasi-particle database manager
%QPkrange # [QPDB]QPDB energy correction( kp1| kp2| bnd1| bnd2| E-Eo[eV]| Img(E)[eV]| Z|)
-1| -1| -1| -1| 0.0| 0.0| 0.0|
%
---------------------------------------------------------------------------

Sincerely,

Dear Guangfu Luo

ypp -q works like this, image you have two bands to whith
you want apply the QP correction the number 3 and 4 and the kpoints 1 2 3 4

1| 4| 3| 3| -0.5| 0.0| 0.0|
1| 4| 4| 4| +1.0| 0.0| 0.0|

the band 3 will be shifted down by 0.5 eV for the kpoints 1,2,3,4
while the band 4 will be shifted up by 1.0 eV for the kpoints 1,2,3,4

Img(E) is the immaginary part of the Self-Energy in case you have it,
but I guess if you have done normal self-consistent GW, you have only the real-part.
Z is the renomalization factor.

Last thing, please download the yambo version on SVN (revision 18)
because we corrected minor bugs

Claudio

Dear Claudio,

Thanks for your explanation and kind reminder.

Sincerely,