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Incorrect unit conversion when using system_2d

Posted: Sat Aug 10, 2024 6:41 am
by MarioKart9
Dear all,

I am runing IBTE calculation on a metallic two dimensional system using EPW-5.8. The results with and without system_2d options are listed as followed.

SYSTEM_2D = .TRUE.
=============================================================================================
Temp Fermi DOS Population SR Conductivity
[K] [eV] [states/Ry] [carriers per cell] [Ohm.cm]^-1
=============================================================================================

100.000 -4.7329 0.79927E+01 0.00000E+00 0.368251E+08 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.364241E+08 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
150.000 -4.7333 0.81619E+01 0.00000E+00 0.174730E+08 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.177691E+08 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
200.000 -4.7335 0.82759E+01 0.00000E+00 0.964927E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.100617E+08 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
250.000 -4.7336 0.83754E+01 0.00000E+00 0.570106E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.599517E+07 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
300.000 -4.7338 0.84947E+01 0.00000E+00 0.354626E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.372990E+07 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
350.000 -4.7339 0.86475E+01 0.00000E+00 0.232844E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.244253E+07 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
400.000 -4.7341 0.88324E+01 0.00000E+00 0.161513E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.168908E+07 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
450.000 -4.7343 0.90352E+01 0.00000E+00 0.117929E+07 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.123008E+07 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
500.000 -4.7345 0.92325E+01 0.00000E+00 0.900787E+06 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.937807E+06 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00

SYSTEM_2D = NO
=============================================================================================
Temp Fermi DOS Population SR Conductivity
[K] [eV] [states/Ry] [carriers per cell] [Ohm.cm]^-1
=============================================================================================

100.000 -4.7329 0.79927E+01 0.00000E+00 0.974350E+06 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.963741E+06 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
150.000 -4.7333 0.81619E+01 0.00000E+00 0.462315E+06 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.470150E+06 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
200.000 -4.7335 0.82759E+01 0.00000E+00 0.255309E+06 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.266221E+06 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
250.000 -4.7336 0.83754E+01 0.00000E+00 0.150844E+06 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.158625E+06 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
300.000 -4.7338 0.84947E+01 0.00000E+00 0.938300E+05 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.986889E+05 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
350.000 -4.7339 0.86475E+01 0.00000E+00 0.616080E+05 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.646266E+05 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
400.000 -4.7341 0.88324E+01 0.00000E+00 0.427346E+05 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.446911E+05 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
450.000 -4.7343 0.90352E+01 0.00000E+00 0.312026E+05 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.325466E+05 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00
500.000 -4.7345 0.92325E+01 0.00000E+00 0.238338E+05 0.000000E+00 0.000000E+00
0.00000E+00 0.000000E+00 0.248133E+05 0.000000E+00
0.00000E+00 0.000000E+00 0.000000E+00 0.000000E+00

Normally, the difference bewteen these two values should be the length of vaccum size, which is 2*10^-7 (cm) in my case (20 angstrom). However, the code seems to unsuccessfully convert bohr to cm and the differece between two values is around 37.7945 (bohr). Also in this case, the unit of conductivity should be ohm-1 not ohm-1cm-1. Maybe I have missed something in my inputs? I am glad anyone can help.

--
&inputepw
prefix = 'c12',
amass(1) = 12.0107
outdir = './outdir'

elph = .true.
! epbwrite = .true.
! epbread = .false.

epwwrite = .false.
epwread = .true.
! kmaps = .true.
selecqread = .true.

nbndsub = 48
! bands_skipped = 'exclude_bands = 1-5'
! fermi_energy =

wannierize = .false.

wdata(1) = 'bands_plot = .true.'
wdata(2) = 'begin kpoint_path'
wdata(3) = 'G 0.00 0.00 0.00 X 0.50 0.00 0.00'
wdata(4) = 'X 0.50 0.00 0.00 S 0.50 0.50 0.00'
wdata(5) = 'S 0.50 0.50 0.00 Y 0.00 0.50 0.00'
wdata(6) = 'Y 0.00 0.50 0.00 G 0.00 0.00 0.00'
wdata(7) = 'end kpoint_path'
wdata(8) = 'bands_plot_format = gnuplot'
wdata(9) = 'dis_num_iter = 3000'
wdata(10)= 'guiding_centres = T'

num_iter = 3000
dis_win_max = 6
! dis_win_min = -6
dis_froz_min= -5.7
dis_froz_max= -3.7
proj(1) = 'C:sp2;pz'

lifc = .true.
asr_typ = 'crystal'

iverbosity = 0
system_2d = gaussian

elecselfen = .false.
phonselfen = .false.

fsthick = 0.4 ! eV
ngaussw = -99
degaussw = 0.0 ! eV

a2f = .false.

dvscf_dir = './epw_cal'

int_mob = .true.
iterative_bte = .true.
scattering = .true.
carrier=.false.
mp_mesh_k = .true.
epmatkqread = .false.
mob_maxiter = 200
broyden_beta = 0.7
restart = .true.
restart_step = 50
selecqread = .false.
nstemp = 9
temps = 100 500
assume_metal = .true.

nkf1 = 96
nkf2 = 72
nkf3 = 1

nqf1 = 96
nqf2 = 72
nqf3 = 1

nk1 = 16
nk2 = 12
nk3 = 1

nq1 = 4
nq2 = 3
nq3 = 1

/

Yours,
Qing