Monolayer MoS2-Gw band structure

[appalakondaiah]

Dear all,

I am very new to Yambo and successful in reproducing the results for tutorials. Now, I am trying for monolayer MoS2 GW band structure and struck with GW band structure, which indeed very strange from PBE in both band profiles as well as band gap( from reported GW result). Here with I am attaching my inputs and kindly suggest me the possible way as well as necessary steps for converging.

with regards
Kondaiah
Sungkyunkwan University
Suwon, South Korea

[Daniele Varsano]

Dear Kondayah,
can you be more explicit? What do you mean by "strange"?
What I can tell you after giving a quick look to your files is that

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NGsBlkXp= 10            RL 

it looks me very out of convergence as well as:

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EXXRLvcs=  60       RL   

may you were meaning to include a cutoff in Rydberg? You should use Ry instead of RL.
Here you are considering very few G vectors (especially in the exchange which is largerly out of convergence for sure).
Moreover please note your considering a coulomb cutoff parameter

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% CUTBox
 0.00     | 0.00     | 30.24     |        # [CUT] [au] Box sides
%

larger than your side of your unit cell which does not make much sense.
Finally as far as I know, for MoS2 you need to include spin-orbit coupling in your ground state calculations.
I suggest you to have a look to the details for GW calculation in MoS2 already published by several group, also using the Yambo code (see e.g. https://journals.aps.org/prb/abstract/1 ... .88.045412).

Best,
Daniele