Yambo Community Forum

Dear all,

I am dealing with a 2d system (which is metallic using DFT and semiconducting considering GW correction).
Can I calculate optical properties using BSE for such system?

My current version is yambo-3.3.0-rev41. After GW calculation, by typing 'yambo -o b -V qp -y d', I got the error as
'[ERROR] STOP signal received while in :[07] Bethe-Salpeter Kernel
[ERROR]Fractional e/h occupations found. BS coupling forced.'

I wonder to know is there any method can be used to fix it? How about using the new version 3.4.0?

Many thanks!
Yan Jiaxu

Dear Waynebeibei,
sure you can use the 3.4, anyway it should work with the previous version too.
If you post your input/report we can try to have a look. It seems that the quasiparticle corrections are not been read correctly.

Best,
Daniele

Sure. Pls find the attached files.

Many thanks for your reply.

Yan Jiaxu

Dear Yan Jiaxu,
the problem here is that you still have fractional occupation number. You should need a self consistent calculation in order to fix them, but this part of the code it is not yet available. In order to avoid the error you could play with the occupation threshold (OccTresh variable). Anyway you should also activate the coupling
term of the BSE. Anyway I'm not expert on that. May be someone can give you more insight on how to solve the problem.

Cheers,
Daniele