EPW Forum

dear EPW developer

during EPW calculation for 2H-NbS2, the calculation of pw.x is right, this is an error report:

- Number of bands is ( 40)
- Number of total bands is ( 40)
- Number of excluded bands is ( 0)
- Number of wannier functions is ( 6)
- All guiding functions are given

Reading data about k-point neighbours

- All neighbours are found

AMN
k points = 324 in 1 pools
1 of 324 on ionode

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Error in routine calbec (3):
size mismatch
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

stopping ...

The input file of EPW contains

--
&inputepw
prefix = 'NbS2',
amass(1) = 92.9064,
amass(2) = 32.065,
outdir = './'

ep_coupling = .true.
elph = .true.
kmaps = .false.
epbwrite = .true.
epbread = .false.

epwwrite = .true.
epwread = .false.

etf_mem = 1

nbndsub = 6,

wannierize = .true.
num_iter = 300


proj(1) = 'S:p'

wdata(1) = 'bands_plot = .true.'
wdata(2) = 'begin kpoint_path'
wdata(3) = 'G 0.00 0.00 0.00 M 0.50 0.00 0.00'
wdata(4) = 'X 0.50 0.00 0.00 K 0.33 0.33 0.00'
wdata(5) = 'end kpoint_path'
wdata(6) = 'bands_plot_format = gnuplot'

iverbosity = 2

eps_acustic = 2.0 ! Lowest boundary for the phonon frequency
ephwrite = .true. ! Writes .ephmat files used when Eliasberg = .true.

fsthick = 0.4 ! eV
degaussw = 0.10 ! eV
nsmear = 1
delta_smear = 0.04 ! eV

degaussq = 0.5 ! meV
nqstep = 500

eliashberg = .true.

laniso = .true.
limag = .true.
lpade = .true.

conv_thr_iaxis = 1.0d-4

wscut = 1.0 ! eV Upper limit over frequency integration/summation in the Elisashberg eq

nstemp = 1 ! Nr. of temps
temps = 2.00 ! K provide list of temperetures OR (nstemp and temps = tempsmin tempsmax for even space mode)

nsiter = 500

muc = 0.16

dvscf_dir = '../Phonon/save'

nk1 = 18
nk2 = 18
nk3 = 1

nq1 = 18
nq2 = 18
nq3 = 1

mp_mesh_k = .true.
nkf1 = 20
nkf2 = 20
nkf3 = 1

nqf1 = 20
nqf2 = 20
nqf3 = 1
/

In the process of EPW running, only nnkp file is generated successfully

Dear yq_zhao:
I guess that you encounter the issue when calculating Amn.
How many Sulfur atoms in your system? If there are more than two Sulfur atoms in your system, " nbndsub = 6 " is not consistent with " proj(1) = 'S:p' ".

I would suggest you to fully understand the example of MgB2 before starting the production run for your research.

Sincerely,

H. Lee

there are four Sulfur atoms in system, should i change nbndsub

Dear yq_zhao:

Yes, if there are four S atoms, you should change the value of nbndsub accordingly.

Sincerely,

H. Lee