Polarisation for AlAs

Total energy, geometry optimization, DFT+U, spin....

Moderator: bguster

Locked
srajpand
Posts: 2
Joined: Wed Aug 01, 2018 5:20 pm

Polarisation for AlAs

Post by srajpand » Wed Aug 01, 2018 5:43 pm

Hi abinit users,

I have been using abinit for various calculations but got an error when trying to calculate Berry phase polarisations for AlAs given in abinit website version 8.4.4.

My input file ,log files are attached below:

On top of that I used same version(8.4.4) of abinit to submit my job.


Could you kindly let me know why I am getting an error?

Thanking in advance.

Best regards,
Suman
Attachments
tffield_1.in
(1.89 KiB) Downloaded 226 times
alas.log
(871.45 KiB) Downloaded 204 times

User avatar
gmatteo
Posts: 291
Joined: Sun Aug 16, 2009 5:40 pm

Re: Polarisation for AlAs

Post by gmatteo » Wed Aug 01, 2018 10:39 pm

--- !ERROR
src_file: m_dtset.F90
src_line: 278
mpi_rank: 0
message: |
Initialization of occ, with occopt= 1
There are not enough bands to get charge balance right
Action: modify input file ...
(check the pseudopotential charges, the variable charge,
and the declared number of bands, nband)
...

You are using a set of pseudopotentials that differ from the one used in the tutorial.

Your calculation uses:

Please give name of formatted atomic psp file
iofn2 : for atom type 1, psp file is ../../Al.psp8

Please give name of formatted atomic psp file
iofn2 : for atom type 2, psp file is ../../As.psp8
read the values zionpsp= 3.0 , pspcod= 8 , lmax= 2
read the values zionpsp= 15.0 , pspcod= 8 , lmax= 2

so there are 18 valence electrons per unit cell in your calculaton (As has semi-core states)
whereas the pseudo for As used in the tutorial has 5 valence electrons

$ abiopen.py ~/git_repos/abinit/tests/Psps_for_tests/33as.pspnc -p
<NcAbinitPseudo: 33as.pspnc>
summary: Troullier-Martins psp for element As Thu Oct 27 17:37:14 EDT 1994
number of valence electrons: 5.0
maximum angular momentum: p
angular momentum for local part: p
XC correlation: LDA_XC_TETER93
supports spin-orbit: False
radius for non-linear core correction: 2.0573171556401
hint for low accuracy: ecut: 0.0, pawecutdg: 0.0
hint for normal accuracy: ecut: 0.0, pawecutdg: 0.0
hint for high accuracy: ecut: 0.0, pawecutdg: 0.0

The input file of the tutorial uses nband = 4 (3 for Al + 5 for As) / 2
while your input file should have nband = (15 + 3) / 2 = 9

HTH
Matteo

srajpand
Posts: 2
Joined: Wed Aug 01, 2018 5:20 pm

Re: Polarisation for AlAs

Post by srajpand » Fri Aug 03, 2018 5:08 am

Hi Gmatteo,

Thank you for your help and really appreciated.

I have one question regarding Berry Phase calculation of polarisation of GeS. In my calculation,

For pseudopotential I have used ONCVPSP (Ge.psp8,S.psp8).

Finally, I was able to get polarisation 0.253 C/m^2 which doesn't match with actual value 1.8 C/m^2 where I have used no of bands 100.

I have an impression there could be error in the no of bands in the input file or something else.

Could you kindly let me know the error in my input files?

Please find the attachment of input and log files.

Thanks in advance.

Best regards,
Suman
Attachments
ges.in
(1.99 KiB) Downloaded 211 times
ges.log
(83.03 KiB) Downloaded 212 times

Locked