Yambo Community Forum

Dear all:
In GW calculations, I know the following five parameters should be tested to be converged:
EXXRLvcs, QpntsRXp, NGsBlkXp, BndsRnXp and GbndRnge

However, when I following the tutorial to issue the command
yambo -b -k hartree -g n -p c
the generated input file has no parameter of QpntsRXp like this:
#
# GPL Version 3.4.1 Revision 3187
# http://www.yambo-code.org
#
em1s # [R Xs] Static Inverse Dielectric Matrix
gw0 # [R GW] GoWo Quasiparticle energy levels
cohsex # [R Xp] COlumb Hole Screened EXchange
HF_and_locXC # [R XX] Hartree-Fock Self-energy and Vxc
EXXRLvcs= 2085 RL # [XX] Exchange RL components
Chimod= "Hartree" # [X] IP/Hartree/ALDA/LRC/BSfxc
% BndsRnXs
1 | 50 | # [Xs] Polarization function bands
%
NGsBlkXs= 1 RL # [Xs] Response block size
% LongDrXs
1.000000 | 0.000000 | 0.000000 | # [Xs] [cc] Electric Field
%
% GbndRnge
1 | 50 | # [GW] G[W] bands range
%
%QPkrange # [GW] QP generalized Kpoint/Band indices
1| 8| 1| 50|
%
%QPerange # [GW] QP generalized Kpoint/Energy indices
1| 8| 0.0|-1.0|
%
Is it reasonable or it should be added manually?
By the way, I get NaN in E-E0 column. What is the possible reason for this fact?


Shijun Zhao
Peking University

Dear Shijun,
in GW you need to use all the Q points in order to integrate in the whole Brilluoin zone, so it is not needed in input.
In order to converge with respect the Qpoints, you need to increase the k points in the ground state calculations.
About the NaN, first note that your input file it is not a GW calculation but a COHSEX run. It is impossible to understand what is going on with the information you provided, beside the input, please post also the report file.
Best,
Daniele