Conduction energy increases

Concerns issues with computing quasiparticle corrections to the DFT eigenvalues - i.e., the self-energy within the GW approximation (-g n), or considering the Hartree-Fock exchange only (-x)

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hammouri
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Conduction energy increases

Post by hammouri » Sun Apr 10, 2022 3:57 pm

In the fig. below the conduction energy increases with increase in the size of the dielectric matrix. The difference in the conduction energy is about 0.3 eV.
In the below input I included up to 100 bands to reach convergence.
If you think converging is achieved please let me know. I decided to go with EXXRLvcs=80 and NGsBlkXp=4.

Code: Select all

[attachment=0]Screen Shot 2022-04-10 at 9.48.15 AM.png[/attachment]

Code: Select all

#                                                                     
#   __   __     _        __  __       ____      U  ___  u             
#   \ \ / / U  /"\  U u |" \/ "| u U | __") u    \/"_ \/              
#    \ V /   \/ _ \/   \| |\/| |/   \|  _ \/     | | | |              
#   U_|"|_u  / ___ \    | |  | |     | |_) | .-,_| |_| |              
#     |_|   /_/   \_\   |_|  |_|     |____/   \_)-\___/               
# .-,//|(_   \\    >>  <<,-,,-.     _|| \\_        \\                 
#  \_) (__) (__)  (__)  (./  \.)   (__) (__)      (__)                
#                                                                     
#                                                                     
#       Version 5.0.4 Revision 19595 Hash 896bffc02                   
#                        Branch is                                    
#                    MPI+HDF5_IO Build                                
#                http://www.yambo-code.org                            
#
HF_and_locXC                     # [R] Hartree-Fock
ppa                          # [R Xp] Plasmon Pole Approximation
gw0                              # [R] GW approximation
em1d                             # [R][X] Dynamically Screened Interaction
EXXRLvcs= 60               Ry    # [XX] Exchange    RL components
VXCRLvcs= 26745            RL    # [XC] XCpotential RL components
Chimod= "HARTREE"                # [X] IP/Hartree/ALDA/LRC/PF/BSfxc
% BndsRnXp
   1 | 40 |                         # [Xp] Polarization function bands
%
NGsBlkXp= 1                Ry    # [Xp] Response block size
% LongDrXp
 1.000000 | 1.000000 | 1.000000 |        # [Xp] [cc] Electric Field
%
PPAPntXp= 27.21138         eV    # [Xp] PPA imaginary energy
XTermKind= "none"                # [X] X terminator ("none","BG" Bruneval-Gonze)
% GbndRnge
   1 | 50 |                         # [GW] G[W] bands range
%
GDamping=  0.10000     eV    # [GW] G[W] damping
dScStep=  0.10000      eV    # [GW] Energy step to evaluate Z factors
DysSolver= "n"                   # [GW] Dyson Equation solver ("n","s","g")
%QPkrange                        # [GW] QP generalized Kpoint/Band indices
1|7|30|31|
%
~ 
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Hammouri, M.
Assistant Professor of Physics
University of Wisconsin
USA

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Daniele Varsano
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Re: Conduction energy increases

Post by Daniele Varsano » Mon Apr 11, 2022 9:07 am

Dear Hammouri,

once you have understood how to perform convergences, it is really up to you to decide if the accuracy you obtained is satisfactory.

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/

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hammouri
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Joined: Fri Feb 09, 2018 11:25 pm

Re: Conduction energy increases

Post by hammouri » Mon Apr 11, 2022 11:25 pm

I followed the tutorial step by step and that was what I got!
Hammouri, M.
Assistant Professor of Physics
University of Wisconsin
USA

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Daniele Varsano
Posts: 3773
Joined: Tue Mar 17, 2009 2:23 pm
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Re: Conduction energy increases

Post by Daniele Varsano » Wed Apr 13, 2022 5:22 am

Dear Hammouri,
sorry but I do not understand what is your question. What you obtain is reasonable.
What I'm saying is that it is up to you to decide the converged parameters considering the accuracy you need and the computational resources available

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/

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