EPW Forum

Dear Nadeem,

Happy to see that it now works for you.

The EPW/tests are not the official tests (its a remain of previous tests and will eventually be removed). In this case you just need to set "kmaps = .true." in epw2.in and epw3.in to make it works (as the error message tells us).

Note that the version 6.1 of quantum espresso is available: http://www.qe-forge.org/gf/project/q-e/ ... kage_id=18

Best,
Samuel

Hi Samuel
Thank You for so much Help !!

Dear users,
I am using epw.x to examine electron phonon coupling in PbI2. already I have gone through tutorial for SiC. But for PbI2 ,as soon as the wannier part gets completed, I get an error
"segmentation fault occurred " . I am giving my epw input file here. can you please help me to fix it ? thanking you in advance



--
&inputepw
prefix ='pbi2',
amass(1) = 207.20000
amass(2) = 126.90447
outdir = './'
dvscf_dir = './save'

elph = .true.
kmaps = .false.
epbwrite = .true.
epbread = .false.
epwwrite = .true.
epwread = .false.
lpolar = .true.

wannierize = .true.
system_2d = .true.
nbndsub = 12
nbndskip = 0

efermi_read= .true.
fermi_energy= -1.03385

dis_win_max = 10.0d0
dis_froz_max = 0.0d0
dis_win_min = -5.0d0
iprint = 2


proj(1)= 'Pb:s'
proj(2)= 'Pb:p'
proj(3)= 'I:s'
proj(4)= 'I:p'
wdata(1) = 'bands_plot = .true.'
wdata(2) = 'begin kpoint_path'
wdata(3) = ' K 0.3333333333 0.3333333333 0.00000 G 0.00000 0.00000 0.00000 '
wdata(4) = ' G 0.00000 0.00000 0.00000 M 0.50000 0.00000 0.00000 '
wdata(5) = ' M 0.50000 0.00000 0.00000 K 0.3333333333 0.3333333333 0.00000 '
wdata(6) = 'end kpoint_path'

elecselfen = .false.
phonselfen = .false.
prtgkk = .true.

a2f = .false.
parallel_k = .true.
parallel_q = .false.
fsthick = 7 ! eV
eptemp = 300 ! K
degaussw = 0.05 ! eV

filqf = 'path.dat'
nkf1 = 1
nkf2 = 1
nkf3 = 1
!nqf1 = 90
!nqf2 = 90
!nqf3 = 1
nk1 = 15
nk2 = 15
nk3 = 1
nq1 = 5
nq2 = 5
nq3 = 1
/
5
0.000000000000000 0.000000000000000 0.000000000000000
0.000000000000000 0.230972210747074 0.000000000000000
0.000000000000000 0.461944421494147 0.000000000000000
0.200027802064237 0.346458316236113 0.000000000000000
0.200027802064237 0.577430526983186 0.000000000000000

I have somethng more to ask.
In my nscf file , I have given nbnd=35, but I am giving only 12 wannier band to plot the band structure and putting nbndskip=0,
is error because of this ? I dont know , please help me

Hello,

Yes it could be that there is a problem at the Wannierization level.

You can check the output of Wannier. The file should be named pbi2.wout. Did it converged ?

Best wishes,
Samuel

thanks for your reply
Actually, one of individual spread was high around 14 (ang. square ) . I am doing it with changing some parameters. I will let you know, once it is done.

Dear users,
I am getting a weird thing in my epw calculation.
When I give uniform fine grid in epw input file to calculate |g|, it is smoothly running, but when I am giving the desired path,
it is giving me an error related to the segmentation fault.
one more thing, after it runs perfectly where I use only uniform fine grid, If I restart this calculation to calculate Imsigma (even if I use unform fine grid) it gives me again the same error.
Please Help me out . thanking you in advance

I am giving you my input file


--
&inputepw
prefix = 'pbi2' ,
amass(1) = 207.20000
amass(2) = 126.90447
outdir = './'
dvscf_dir = './save'
elph = .true.
kmaps = .false.
epbwrite = .true.
epbread = .false.
epwwrite = .true.
epwread = .false.
lpolar = .true.
wannierize = .true.
system_2d = .true.
nbndsub = 12
nbndskip = 0

efermi_read= .true.
fermi_energy= -1.03385

dis_win_max = 10.0d0
dis_froz_max = 0.0d0
dis_win_min = -5.0d0
iprint = 2



num_iter = 5000

proj(1)= 'Pb:s'
proj(2)= 'Pb:p'
proj(3)= 'I:s'
proj(4)= 'I:p'

elecselfen = .false.
phonselfen = .false.
prtgkk = .true.

a2f = .false.
parallel_k = .true.
parallel_q = .false.
fsthick = 8 ! eV
eptemp = 300 ! K
degaussw = 0.05 ! eV

filqf ='path.dat'
nkf1 = 1
nkf2 = 1
nkf3 = 1
nk1 = 15
nk2 = 15
nk3 = 1
nq1 = 5
nq2 = 5
nq3 = 1
/
5 cartesian
0.000000000000000 0.000000000000000 0.000000000000000
0.000000000000000 0.230972210747074 0.000000000000000
0.000000000000000 0.461944421494147 0.000000000000000
0.200027802064237 0.346458316236113 0.000000000000000
0.200027802064237 0.577430526983186 0.000000000000000

and the error is

forrtl: severe (151): allocatable array is already allocated
Image PC Routine Line Source
epw.x 0000000000E957DC Unknown Unknown Unknown
epw.x 0000000000445E15 ephwann_shuffle_ 234 ephwann_shuffle.f90
epw.x 0000000000442207 elphon_shuffle_wr 764 elphon_shuffle_wrap.f90
epw.x 000000000040A185 MAIN__ 150 epw.f90
epw.x 00000000004094DE Unknown Unknown Unknown
libc-2.12.so 00002ACFAE299D1D __libc_start_main Unknown Unknown
epw.x 00000000004093E9 Unknown Unknown Unknown
forrtl: error (69): process interrupted (SIGINT)
Image PC Routine Line Source
epw.x 0000000000E4EB30 Unknown Unknown Unknown
libpthread-2.12.s 00002B0B289BB710 Unknown Unknown Unknown
libmpi.so.12 00002B0B27EE127D PMPIDI_CH3I_Progr Unknown Unknown
libmpi.so.12 00002B0B27FEDC29 MPIC_Wait Unknown Unknown
libmpi.so.12 00002B0B27FED922 MPIC_Sendrecv Unknown Unknown
libmpi.so.12 00002B0B27EC6E55 MPIR_Barrier_intr Unknown Unknown
libmpi.so.12 00002B0B27EC6875 I_MPIR_Barrier_in Unknown Unknown
libmpi.so.12 00002B0B27EC66CC MPIR_Barrier Unknown Unknown
libmpi.so.12 00002B0B27EC65FC MPIR_Barrier_impl Unknown Unknown
libmpi.so.12 00002B0B27EC8482 PMPI_Barrier Unknown Unknown
libmpifort.so.12. 00002B0B27A8F38C pmpi_barrier Unknown Unknown
epw.x 0000000000C2F6E7 bcast_integer_ 37 mp_base.f90
epw.x 0000000000C13888 mp_mp_mp_bcast_i1 293 mp.f90
epw.x 000000000044602E ephwann_shuffle_ 243 ephwann_shuffle.f90
epw.x 0000000000442207 elphon_shuffle_wr 764 elphon_shuffle_wrap.f90
epw.x 000000000040A185 MAIN__ 150 epw.f90
epw.x 00000000004094DE Unknown Unknown Unknown
libc-2.12.so 00002B0B28E6BD1D __libc_start_main Unknown Unknown
epw.x 00000000004093E9 Unknown Unknown Unknown

Dear vinpandey,

Seems there is an issue with the EPW version you are using (array already allocated). Which version are you using and what is at (and around) line 234 of the q-e/EPW/src/ephwann_shuffle.f90 file ?
In the most recent version of EPW it is just a variable declaration so its probably not that.

PS: Can you try with the most recent QE/EPW version that you can get with:
git clone https://gitlab.com/QEF/q-e.git

Best wishes,
Samuel