Dear developer,
I am trying to calculate the G0W0 direct gap at the gamma point of solid Li2O2. I am getting a value of ~5.28 eV which is a little bit higher than the reported value of 4.81 eV (https://doi.org/10.1063/1.3645544) . However, I'm finding a PBE gap of ~1.92 eV which is in good agreement with the PBE gap of 1.94 eV reported in the same paper.
I was wondering if you could kindly take a look at the attached input and output files and let me know what you think I might be doing wrong. I ran a calculation with lower VXCRLvcs, EXXRLvcs (=24365 RL) and lower NGsBlkXp (=20) but the gap doesn't seem to change much.
Eagerly awaiting your reply,
Subhayan
Slightly high G0W0 quasiparticle gap
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Slightly high G0W0 quasiparticle gap
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Subhayan Roychoudhury
Postdoctoral researcher
Lawrence Berkeley National Laboratory
Postdoctoral researcher
Lawrence Berkeley National Laboratory
- Daniele Varsano
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Re: Slightly high G0W0 quasiparticle gap
Dear Subhayan,
my suggestion is a careful check on the convergence, the used number of bands (54) seems to be quite small considering you have 14 occupied bands. I would run calculations using
100-200-300 bands to check the convergence.
Moreover, also the NGsBlkXp=25RL is unusually small, again I will check the convergence considering 200-400-600 RL and so on.
Best,
Daniele
my suggestion is a careful check on the convergence, the used number of bands (54) seems to be quite small considering you have 14 occupied bands. I would run calculations using
100-200-300 bands to check the convergence.
Moreover, also the NGsBlkXp=25RL is unusually small, again I will check the convergence considering 200-400-600 RL and so on.
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/
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/
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- Posts: 32
- Joined: Thu Sep 26, 2019 7:48 am
Re: Slightly high G0W0 quasiparticle gap
Hi Daniele,
Thanks a lot. I'll try that.
Best regards,
Subhayan
Thanks a lot. I'll try that.
Best regards,
Subhayan
Subhayan Roychoudhury
Postdoctoral researcher
Lawrence Berkeley National Laboratory
Postdoctoral researcher
Lawrence Berkeley National Laboratory
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- Posts: 32
- Joined: Thu Sep 26, 2019 7:48 am
Re: Slightly high G0W0 quasiparticle gap
This fixes the issue. Thanks a lot.
Subhayan Roychoudhury
Postdoctoral researcher
Lawrence Berkeley National Laboratory
Postdoctoral researcher
Lawrence Berkeley National Laboratory