MoS2 spectrum : strange result
Posted: Mon Sep 04, 2017 3:33 pm
I am computing the spectrum of monolayer MoS2, including spin-orbit effects, on top of correctly converged GW corrections. The result is nice, but not exactly as expected. The spectrum has the right shape, but the exciton peaks seem too broad, compared to theoretical and experimental results from the literature. (for example, PHYSICAL REVIEW B 93, 155435 (2016) and PHYSICAL REVIEW B 86, 115409 (2012))
Here is the input :
Is there some kind of broadening parameter I should set somewhere ? Is the electric field in the right direction ? Do I need more bands around the gap to converge ?
BTW, I'm sorry for requesting that, but I also have a problem with the YPP utility that I posted on that part of the forum, and I haven´t had any answer yet.
Thanks in advance
Here is the input :
Code: Select all
#
# __ __ ________ ___ __ __ _______ ______
# /_/\/_/\ /_______/\ /__//_//_/\ /_______/\ /_____/\
# \ \ \ \ \\::: _ \ \\::\| \| \ \\::: _ \ \\:::_ \ \
# \:\_\ \ \\::(_) \ \\:. \ \\::(_) \/_\:\ \ \ \
# \::::_\/ \:: __ \ \\:.\-/\ \ \\:: _ \ \\:\ \ \ \
# \::\ \ \:.\ \ \ \\. \ \ \ \\::(_) \ \\:\_\ \ \
# \__\/ \__\/\__\/ \__\/ \__\/ \_______\/ \_____\/
#
#
# GPL Version 4.1.2 Revision 120
# MPI Build
# http://www.yambo-code.org
#
optics # [R OPT] Optics
em1s # [R Xs] Static Inverse Dielectric Matrix
bss # [R BSS] Bethe Salpeter Equation solver
bse # [R BSE] Bethe Salpeter Equation.
bsk # [R BSK] Bethe Salpeter Equation kernel
#em1d # [R Xd] Dynamical Inverse Dielectric Matrix
#ppa # [R Xp] Plasmon Pole Approximation
Chimod= "hartree" # [X] IP/Hartree/ALDA/LRC/BSfxc
BSEmod= "retarded" # [BSE] resonant/retarded/coupling
BSKmod= "SEX" # [BSE] IP/Hartree/HF/ALDA/SEX
BSSmod= "d" # [BSS] (h)aydock/(d)iagonalization/(i)nversion/(t)ddft`
BSENGexx= 38000 mHa # [BSK] Exchange components
BSENGBlk= 8000 mHa # [BSK] Screened interaction block size
NLogCPUs=0 # [PARALLEL] Live-timing CPU`s (0 for all)
X_all_q_CPU= "1 2 68 1" # [PARALLEL] CPUs for each role
X_all_q_ROLEs= "q k c v" # [PARALLEL] CPUs roles (q,k,c,v)
X_all_q_nCPU_LinAlg_INV= 1 # [PARALLEL] CPUs for Linear Algebra
SE_CPU= "1 2 68" # [PARALLEL] CPUs for each role
SE_ROLEs= "q qp b" # [PARALLEL] CPUs roles (q,qp,b)
BS_CPU= "136 1 1" # [PARALLEL] CPUs for each role
BS_ROLEs= "k eh t" # [PARALLEL] CPUs roles (k,eh,t)
BS_nCPU_invert= 1 # [PARALLEL] CPUs for matrix inversion
BS_nCPU_diago= 1 # [PARALLEL] CPUs for matrix diagonalization
#WehCpl # [BSK] eh interaction included also in coupling
RandQpts=1000000 # [RIM] Number of random q-points in the BZ
RandGvec= 1000 mHa # [RIM] Coulomb interaction RS components
CUTGeo= "box Z" # [CUT] Coulomb Cutoff geometry: box/cylinder/sphere X/Y/Z/XY..
% CUTBox
0.00 | 0.00 | 25.00 | # [CUT] [au] Box sides
%
KfnQPdb= "E < SAVE/ndb.QP" # [EXTQP BSK BSS] Database
% BEnRange
0.00000 | 10.00000 | eV # [BSS] Energy range
%
% BDmRange
0.10000 | 0.10000 | eV # [BSS] Damping range
%
BEnSteps= 1000 # [BSS] Energy steps
% BLongDir
1.000000 | 0.000000 | 0.000000 | # [BSS] [cc] Electric Field
%
% BSEBands
25 | 28 | # [BSK] Bands range !plus après
%
% BndsRnXs
1 | 200 | # [Xs] Polarization function bands
%
NGsBlkXs=8000 mHa # [Xs] Response block size
% DmRngeXs
0.10000 | 0.10000 | eV # [Xs] Damping range
%
% LongDrXs
1.000000 | 0.000000 | 0.000000 | # [Xs] [cc] Electric Field
%
BTW, I'm sorry for requesting that, but I also have a problem with the YPP utility that I posted on that part of the forum, and I haven´t had any answer yet.
Thanks in advance