GW Band structure changes caused by QP correction

[CJS]

Dear all,

After performing standard SCF and NSCF calculations with Quantum ESPRESSO, I carried out a G₀W₀ quasiparticle band calculation with Yambo and interpolated the band structure using ypp_bands.in. The results show a severe distortion of the band structure after applying the QP correction. Specifically, the conduction band corrections near the Gamma point are much smaller than those in other regions, leading to a strongly deformed band structure. What could be the reason for this?

I have attached the following for reference:

Band structure with and without QP correction

Input files: gw_ppa_all_Bz.in and ypp_bands.in

Yours
chenjiashu
Master student, Xiangtan University

[Daniele Varsano]

Dear Chenjiashu,

this is due to interpolation problem of ypp that in some cases is not accurate enough.
My suggestion is to perform the interpolation using the yambopy utility which is much more accurate:
Here you can find a tutorial:
https://wiki.yambo-code.eu/wiki/index.p ... structures


Best,
Daniele