Dear developer,
I am trying to run a BSE calculation on a slightly distorted (actually from a molecular-dynamics snapshot) methanol molecule. However, I am getting negative excitation energies for the first two excitations. I guess this has to do with the fact that, in the output of the GW calculation, I am getting E-Eo= 21.49 (Eo=-20.33 , E=1.16) for the first quasiparticle orbital. Could you kindly take a look at the attached files and let me know your thoughts?
For the GW calculation: the input is GW_input.in and the output is r_em1d_ppa_HF_and_locXC_gw0_rim_cut
For the BSE calculation: the input is 02_BSE_construct_solve.in and the output is r-3D_BSE_optics_bse_bss_dipoles_em1s_rim_cut
Kindly let me know if you need any other files.
Best regards,
Subhayan
Very high QP eigenvalue for lowest orbital
Moderators: Davide Sangalli, andrea.ferretti, myrta gruning, andrea marini, Daniele Varsano
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Very high QP eigenvalue for lowest orbital
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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: Very high QP eigenvalue for lowest orbital
Dear Subhayan,
yes, the problem is that the QP energy of the first deep state is not calculated properly. The problem is the Z factor:
It would be possible to investigate it, e.g. some instability in the self-energy derivative for this deep state, but it is not straightforward, you could see for instance the effect
of reducing the dScStep variable.
Anyway, I think that it is not relevant to include such a deep state in the BSE and I would remove the first states from the BSEBands.
Please also check your CUTRadius that seems a bit small.
Best,
Daniele
yes, the problem is that the QP energy of the first deep state is not calculated properly. The problem is the Z factor:
Code: Select all
B=1 Eo=-20.33 E= 1.16 E-Eo= 21.49 Re(Z)=**** Im(Z)= -2.05918 nlXC=-31.45032 lXC=-19.44300 So= 7.05307
of reducing the dScStep variable.
Anyway, I think that it is not relevant to include such a deep state in the BSE and I would remove the first states from the BSEBands.
Please also check your CUTRadius that seems a bit small.
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: Very high QP eigenvalue for lowest orbital
Perfect. Thanks a lot
Subhayan Roychoudhury
Postdoctoral researcher
Lawrence Berkeley National Laboratory
Postdoctoral researcher
Lawrence Berkeley National Laboratory