Could anyone tell me how to write the right codes and execute the right
commands to get the matrix elelments from the valence bands to the
conduction bands at the Brilloun Zone in Quantum espresso?
Thank you very much!
Best regards,
Jingjing
-------- Forwarded Message --------
Subject: [Extern] [QE-users] how to extract the matrix elements from
the valence bands to conduction bandsat the Brillouin zone center?
Date: Thu, 9 Nov 2023 23:43:53 +0100
From: Yu, Jingjing <[email protected]>
Reply-To: Quantum ESPRESSO users Forum <[email protected]>
To: [email protected]
Hello everyone,
I am wondering how to extract the matrix elements from the valence bands
to the conduction bands at the Brillouin zone center, Gamma point in
Quantum espresso.
I tried to calculate the matrix elements of Si and I got the result in
the p_avg.dat. But it looks weird, because the the corresponding matrix
elements along x, y ,z directions (for example, three values |/M/_11 |^2
along x.y,z directions) are totally different shown below.
*&p_mat nbnd= 6, nks= 29 /
0.000000 0.000000 0.000000 4
1
0.00022045 0.02823071 0.03700090 0.13449672
0.00458980 0.00203767 0.00400515 0.00964742
2
0.00327610 0.02056865 0.04947954 0.00093171
0.00019941 0.07363126 0.09566180 0.03136617
3
0.00146403 0.07631971 0.06399219 0.00701410
0.00016914 0.00944635 0.02901511 0.16348040*
Because Si has face-centered cubic crystal structure and the matrix
elements located at the same positions along x, y, z directions should
be same, right?
My general calculation procedures are shown below:
*1. run scf.in*
&control
calculation = 'scf'
restart_mode='from_scratch'
prefix = 'si'
outdir = './outdir'
pseudo_dir = '/home/yyb/qe-7.0/pseudo'
/
&system
ibrav=2, celldm(1) =10.410909236,
nat=2, ntyp=1,
ecutwfc=40
ecutrho=320
nbnd=6
occupations='smearing', smearing='gaussian',degauss=0.005
!nosym = .true.
!noinv = .true.
!occupations = 'fixed'
!input_dft = 'gaupbe'
!nqx1 = 4, nqx2 = 4, nqx3 = 4,
!x_gamma_extrapolation = .false.
! exxdiv_treatment = 'none'
/
&electrons
conv_thr=1e-10
/
ATOMIC_SPECIES
Si 28.0855 Si_ONCV_PBE-1.0.upf
ATOMIC_POSITIONS (alat)
Si 0.00 0.00 0.00
Si 0.25 0.25 0.25
K_POINTS (automatic)
8 8 8 0 0 0
*2.run bands.x*
&bands
outdir='./outdir/'
prefix='si'
filband='si.bands.dat'
lp=.true.
filp = 'p_avg.dat'
/
I don't know how to get the right result and could anyone who has the
experience give me some help or suggestions?_______________________________________________
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_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
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_______________________________________________
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
