[Pw_forum] Problem on HSE bandgap caluculation
sanjaynayak at jncasr.ac.in
sanjaynayak at jncasr.ac.in
Thu Jun 15 10:52:34 CEST 2017
First check the band-structure in bulk case. The smaller band-gap may be
due to appearance of surface states in band-gap region.
----- Original Message -----
From: "LEUNG Clarence" <liangxy123 at hotmail.com>
To: "pw forum" <pw_forum at pwscf.org>
Sent: Thursday, June 15, 2017 1:55:03 PM
Subject: [Pw_forum] Problem on HSE bandgap caluculation
Dear All,
Now, I want to use HSE functional to calculate the band structure of monolayer arsenic, but the band gap is much smaller than previous report (2eV).
I have try to change some parameters. But the results are not good.
EXX= 0.25, ecutwfc=30, gap=1.15eV,
EXX=0.35, ecutwfc=30, gap=0.89eV,
EXX=0.15, ecutwfc=30, gap=1.40eV,
EXX=0.10, ecutwfc=30, gap=1.56eV,
EXX=0.05, ecutwfc=30, gap=1.63eV,
EXX=0.25, ecutwfc=60, gap=1.15eV,
The psudo-potential is norm-conserving:
As 74.921600d0 As.pbe-mt_fhi.UPF
And the input file as follow:
&CONTROL
calculation='scf' ,
verbosity='low',
etot_conv_thr = 1.0D-5 ,
forc_conv_thr = 1.0D-4 ,
nstep = 200 ,
tstress = .false. ,
tprnfor = .false. ,
max_seconds = 320000 ,
wf_collect = .true. ,
/
&SYSTEM
ibrav=0,
celldm(1)=27.2266448794d0,
nat=32,
ntyp=1,
ecutwfc=30,
input_dft='hse',
occupations='smearing',
smearing = 'gaussian' ,
degauss = 0.02 ,
nosym = .true. ,
vdw_corr = 'DFT-D' ,
nqx1 = 1,
nqx2 = 1 ,
nqx3 = 1 ,
exx_fraction = 0.05,
/
&ELECTRONS
conv_thr=1d-06,
mixing_beta=0.3d0,
electron_maxstep = 1000 ,
/
&IONS
ion_dynamics = 'bfgs',
bfgs_ndim = 3 ,
/
ATOMIC_SPECIES
As 74.921600d0 As.pbe-mt_fhi.UPF
ATOMIC_POSITIONS {crystal}
As 0.083333304 0.041666531 0.465177578
As 0.166666686 0.208333294 0.534822422
As 0.083333418 0.291666706 0.465177578
As 0.166666800 0.458333469 0.534822384
As 0.333333200 0.041666531 0.465177578
As 0.416666582 0.208333294 0.534822422
As 0.333333366 0.291666706 0.465177578
As 0.416666748 0.458333469 0.534822384
As 0.083333304 0.541666531 0.465177578
As 0.166666686 0.708333294 0.534822422
As 0.083333418 0.791666706 0.465177578
As 0.166666800 0.958333469 0.534822384
As 0.333333200 0.541666531 0.465177578
As 0.416666582 0.708333294 0.534822422
As 0.333333366 0.791666706 0.465177578
As 0.416666748 0.958333469 0.534822384
As 0.583333304 0.041666531 0.465177578
As 0.666666686 0.208333294 0.534822422
As 0.583333418 0.291666706 0.465177578
As 0.666666800 0.458333469 0.534822384
As 0.833333200 0.041666531 0.465177578
As 0.916666582 0.208333294 0.534822422
As 0.833333366 0.291666706 0.465177578
As 0.916666748 0.458333469 0.534822384
As 0.583333304 0.541666531 0.465177578
As 0.666666686 0.708333294 0.534822422
As 0.583333418 0.791666706 0.465177578
As 0.666666800 0.958333469 0.534822384
As 0.833333200 0.541666531 0.465177578
As 0.916666582 0.708333294 0.534822422
As 0.833333366 0.791666706 0.465177578
As 0.916666748 0.958333469 0.534822384
K_POINTS
84
0.0000000 0.0000000 0.0000000 0.03125
0.0000000 0.1443377 0.0000000 0.06250
0.0000000 0.2886754 0.0000000 0.06250
0.0000000 0.4330131 0.0000000 0.06250
0.0000000 -0.5773508 0.0000000 0.03125
0.1250000 0.0721689 0.0000000 0.0625
0.1250000 0.2165066 0.0000000 0.0625
0.1250000 0.3608443 0.0000000 0.0625
0.1250000 0.5051820 0.0000000 0.0625
0.1250000 -0.5051820 0.0000000 0.0625
0.1250000 -0.3608443 0.0000000 0.0625
0.1250000 -0.2165066 0.0000000 0.0625
0.1250000 -0.0721689 0.0000000 0.0625
0.2500000 0.1443377 0.0000000 0.0625
0.2500000 0.2886754 0.0000000 0.0625
0.2500000 0.4330131 0.0000000 0.0625
0.2500000 0.5773508 0.0000000 0.0625
0.2500000 -0.4330131 0.0000000 0.0625
0.2500000 -0.2886754 0.0000000 0.0625
0.2500000 -0.1443377 0.0000000 0.0625
0.2500000 0.0000000 0.0000000 0.0625
0.3750000 0.2165066 0.0000000 0.0625
0.3750000 0.3608443 0.0000000 0.0625
0.3750000 0.5051820 0.0000000 0.0625
0.3750000 0.6495197 0.0000000 0.0625
0.3750000 -0.3608443 0.0000000 0.0625
0.3750000 -0.2165066 0.0000000 0.0625
0.3750000 -0.0721689 0.0000000 0.0625
0.3750000 0.0721689 0.0000000 0.0625
-0.500000 -0.2886754 0.0000000 0.03125
-0.500000 -0.1443377 0.0000000 0.0625
-0.500000 0.0000000 0.0000000 0.0625
-0.500000 0.1443377 0.0000000 0.0625
-0.500000 -0.8660262 0.0000000 0.03125
0.0000000000 0.0000000000 0.0000000000 0
0.0277777778 0.0000000000 0.0000000000 0
0.0555555556 0.0000000000 0.0000000000 0
0.0833333333 0.0000000000 0.0000000000 0
0.1111111111 0.0000000000 0.0000000000 0
0.1388888889 0.0000000000 0.0000000000 0
0.1666666667 0.0000000000 0.0000000000 0
0.1944444444 0.0000000000 0.0000000000 0
0.2222222222 0.0000000000 0.0000000000 0
0.2500000000 0.0000000000 0.0000000000 0
0.2777777778 0.0000000000 0.0000000000 0
0.3055555556 0.0000000000 0.0000000000 0
0.3333333333 0.0000000000 0.0000000000 0
0.3611111111 0.0000000000 0.0000000000 0
0.3888888889 0.0000000000 0.0000000000 0
0.4166666667 0.0000000000 0.0000000000 0
0.4444444444 0.0000000000 0.0000000000 0
0.4722222222 0.0000000000 0.0000000000 0
0.5000000000 0.0000000000 0.0000000000 0
0.4833330000 0.0333330000 0.0000000000 0
0.4666660000 0.0666660000 0.0000000000 0
0.4499990000 0.0999990000 0.0000000000 0
0.4333320000 0.1333320000 0.0000000000 0
0.4166650000 0.1666650000 0.0000000000 0
0.3999980000 0.1999980000 0.0000000000 0
0.3833310000 0.2333310000 0.0000000000 0
0.3666640000 0.2666640000 0.0000000000 0
0.3499970000 0.2999970000 0.0000000000 0
0.3333300000 0.3333300000 0.0000000000 0
0.3174571429 0.3174571429 0.0000000000 0
0.3015842857 0.3015842857 0.0000000000 0
0.2857114286 0.2857114286 0.0000000000 0
0.2698385714 0.2698385714 0.0000000000 0
0.2539657143 0.2539657143 0.0000000000 0
0.2380928571 0.2380928571 0.0000000000 0
0.2222200000 0.2222200000 0.0000000000 0
0.2063471429 0.2063471429 0.0000000000 0
0.1904742857 0.1904742857 0.0000000000 0
0.1746014286 0.1746014286 0.0000000000 0
0.1587285714 0.1587285714 0.0000000000 0
0.1428557143 0.1428557143 0.0000000000 0
0.1269828571 0.1269828571 0.0000000000 0
0.1111100000 0.1111100000 0.0000000000 0
0.0952371429 0.0952371429 0.0000000000 0
0.0793642857 0.0793642857 0.0000000000 0
0.0634914286 0.0634914286 0.0000000000 0
0.0476185714 0.0476185714 0.0000000000 0
0.0317457143 0.0317457143 0.0000000000 0
0.0158728571 0.0158728571 0.0000000000 0
0.0000000000 0.0000000000 0.0000000000 0
CELL_PARAMETERS {alat}
1.000000000000d0 0.000000000000d0 0.000000000000d0
-0.500000000000d0 0.866024603476d0 0.000000000000d0
0.000000000000d0 0.000000000000d0 1.388144689097d0
Best regards,
Clarence
CityU university of Hong Kong
_______________________________________________
Pw_forum mailing list
Pw_forum at pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum
More information about the users
mailing list