results difference between epw5.1 and epw5.2
Posted: Fri Jul 31, 2020 4:05 am
Dear EPW developers,
I run EPW5.2(qe6.5) and EPW5.1(qe6.4.1) with the completely same input files(scf.in, nscf.in, epw.in, phonon/save) to get the e-p vertex,
but the phonon frequency of two versions in output files can be very different, up to ~7cm-1(~0.9meV)at some q points.
Following is the epw.in in two calculations:
--
&inputepw
system_2d = .true.
lpolar = .true.
lifc = .true.
asr_typ = 'simple'
prefix = 'MoTe2'
amass(1) = 95.96
amass(2) = 127.6
outdir = './'
dvscf_dir = '../phonon/save'
filukk = 'MoTe2.ukk'
iverbosity = 0
etf_mem = 2
ep_coupling = .true.
elph = .true.
use_ws = .true.
num_iter = 2000
iprint = 2
proj(1) = 'Mo:l=2'
proj(2) = 'Te:l=1'
nbndsub = 22
nbndskip = 32
dis_win_min = -8
dis_win_max = 10
dis_froz_min= -2
dis_froz_max= 4.1
efermi_read = .true.
fermi_energy= 1.0253
fsthick = 3 ! eV
eptemp = 300 ! K (same as PRB 76, 165108)
degaussw = 0.005 ! eV
degaussq = 0.01 ! meV
wdata(1) = 'guiding_centres=.true.'
wdata(2) = 'use_ws_distance = .true.'
wdata(3) = 'dis_mix_ratio = 0.5'
wdata(4) = 'dis_num_iter = 2000'
wdata(5) = 'conv_window = 3'
wdata(6) = 'trial_step = 1.0'
epbwrite = .true.
epbread = .false.
epwwrite = .true.
epwread = .false.
kmaps = .false.
wannierize = .true.
prtgkk = .true.
nkf1 = 45
nkf2 = 45
nkf3 = 1
nqf1 = 45
nqf2 = 45
nqf3 = 1
nk1 = 16
nk2 = 16
nk3 = 1
nq1 = 8
nq2 = 8
nq3 = 1
/
10 {cartesian}
0.000000000000000E+00 0.000000000000000E+00 0.000000000000000E+00
0.000000000000000E+00 0.144337567297396E+00 0.000000000000000E+00
0.000000000000000E+00 0.288675134594792E+00 0.000000000000000E+00
0.000000000000000E+00 0.433012701892189E+00 0.000000000000000E+00
0.000000000000000E+00 -0.577350269189585E+00 0.000000000000000E+00
0.125000000000000E+00 0.216506350946094E+00 0.000000000000000E+00
0.125000000000000E+00 0.360843918243491E+00 0.000000000000000E+00
0.125000000000000E+00 0.505181485540887E+00 0.000000000000000E+00
0.250000000000000E+00 0.433012701892189E+00 0.000000000000000E+00
0.250000000000000E+00 0.577350269189585E+00 0.000000000000000E+00
I noticed that dmedate.fmt in EPW5.1 has gone and is replaced by vmedate.fmt in EPW5.2 (maybe they are the same thing in a physical sense).
It is strange that dmedate.fmt file is normal as follows:
(5.136796004771528E-006,2.272028861662918E-005)
(2.892201462303629E-006,-1.226356373239952E-006)
(1.782074204963529E-011,-2.369778190474230E-011)
(-4.154739721377699E-006,1.056601084293195E-011)
(4.850202537877077E-012,4.322976548843746E-007)
(2.038068391136785E-011,-6.021966268537016E-012)
(-1.799612482102541E-006,2.015288205219882E-005)
(-6.975830618110693E-006,-8.136778270005097E-006)
(-1.336234596050945E-011,8.134634011961389E-012)
(-1.329297411725360E-005,-3.512722917950183E-005)
while all in vmedate.fmt is zero as follows:
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
What can be the reason why the phonon frequency has a such big difference w.r.t the same input files?
Did I miss something in the latest version EPW5.2 that leads to the zero vmedate.fmt?
I run EPW5.2(qe6.5) and EPW5.1(qe6.4.1) with the completely same input files(scf.in, nscf.in, epw.in, phonon/save) to get the e-p vertex,
but the phonon frequency of two versions in output files can be very different, up to ~7cm-1(~0.9meV)at some q points.
Following is the epw.in in two calculations:
--
&inputepw
system_2d = .true.
lpolar = .true.
lifc = .true.
asr_typ = 'simple'
prefix = 'MoTe2'
amass(1) = 95.96
amass(2) = 127.6
outdir = './'
dvscf_dir = '../phonon/save'
filukk = 'MoTe2.ukk'
iverbosity = 0
etf_mem = 2
ep_coupling = .true.
elph = .true.
use_ws = .true.
num_iter = 2000
iprint = 2
proj(1) = 'Mo:l=2'
proj(2) = 'Te:l=1'
nbndsub = 22
nbndskip = 32
dis_win_min = -8
dis_win_max = 10
dis_froz_min= -2
dis_froz_max= 4.1
efermi_read = .true.
fermi_energy= 1.0253
fsthick = 3 ! eV
eptemp = 300 ! K (same as PRB 76, 165108)
degaussw = 0.005 ! eV
degaussq = 0.01 ! meV
wdata(1) = 'guiding_centres=.true.'
wdata(2) = 'use_ws_distance = .true.'
wdata(3) = 'dis_mix_ratio = 0.5'
wdata(4) = 'dis_num_iter = 2000'
wdata(5) = 'conv_window = 3'
wdata(6) = 'trial_step = 1.0'
epbwrite = .true.
epbread = .false.
epwwrite = .true.
epwread = .false.
kmaps = .false.
wannierize = .true.
prtgkk = .true.
nkf1 = 45
nkf2 = 45
nkf3 = 1
nqf1 = 45
nqf2 = 45
nqf3 = 1
nk1 = 16
nk2 = 16
nk3 = 1
nq1 = 8
nq2 = 8
nq3 = 1
/
10 {cartesian}
0.000000000000000E+00 0.000000000000000E+00 0.000000000000000E+00
0.000000000000000E+00 0.144337567297396E+00 0.000000000000000E+00
0.000000000000000E+00 0.288675134594792E+00 0.000000000000000E+00
0.000000000000000E+00 0.433012701892189E+00 0.000000000000000E+00
0.000000000000000E+00 -0.577350269189585E+00 0.000000000000000E+00
0.125000000000000E+00 0.216506350946094E+00 0.000000000000000E+00
0.125000000000000E+00 0.360843918243491E+00 0.000000000000000E+00
0.125000000000000E+00 0.505181485540887E+00 0.000000000000000E+00
0.250000000000000E+00 0.433012701892189E+00 0.000000000000000E+00
0.250000000000000E+00 0.577350269189585E+00 0.000000000000000E+00
I noticed that dmedate.fmt in EPW5.1 has gone and is replaced by vmedate.fmt in EPW5.2 (maybe they are the same thing in a physical sense).
It is strange that dmedate.fmt file is normal as follows:
(5.136796004771528E-006,2.272028861662918E-005)
(2.892201462303629E-006,-1.226356373239952E-006)
(1.782074204963529E-011,-2.369778190474230E-011)
(-4.154739721377699E-006,1.056601084293195E-011)
(4.850202537877077E-012,4.322976548843746E-007)
(2.038068391136785E-011,-6.021966268537016E-012)
(-1.799612482102541E-006,2.015288205219882E-005)
(-6.975830618110693E-006,-8.136778270005097E-006)
(-1.336234596050945E-011,8.134634011961389E-012)
(-1.329297411725360E-005,-3.512722917950183E-005)
while all in vmedate.fmt is zero as follows:
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
(0.000000000000000E+000,0.000000000000000E+000)
What can be the reason why the phonon frequency has a such big difference w.r.t the same input files?
Did I miss something in the latest version EPW5.2 that leads to the zero vmedate.fmt?