how to run epw

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habiba

how to run epw

Post by habiba »

Dear epw user,

I want to know the steps necessary to run epw code with Quantum espresso.
I start with:
scf calculation
nscf calculation
phonon calculation using ph.x
and then dynmat.x
then scf_epw using pw.x
then nscf_epw using pw.x
and finaly epw.x

is that correct, or i missed other steps.
best regards.

sponce
Site Admin
Posts: 616
Joined: Wed Jan 13, 2016 7:25 pm
Affiliation: EPFL

Re: how to run epw

Post by sponce »

Hello,

Typical steps is as follow:

scf calculation
phonon calculation using ph.x
python pp.py (post processing to get the correct files inside the "save" folder)
then scf_epw using pw.x
then nscf_epw using pw.x
and finaly epw.x

Best,
Samuel
Prof. Samuel Poncé
Chercheur qualifié F.R.S.-FNRS / Professeur UCLouvain
Institute of Condensed Matter and Nanosciences
UCLouvain, Belgium
Web: https://www.samuelponce.com

rajneesh chaurasiya
Posts: 1
Joined: Sun Dec 31, 2017 6:21 am
Affiliation:

error in MgB2 tutorial

Post by rajneesh chaurasiya »

Dear EPW users,

I have coupled EPW code in the quantum espresso version 6.2.1 using fortran compiler and trying to repeat MgB2 tutorial.

So for repetition, I followed similar procedure as mention in the tutorial but could not reproduced. Upto phonon calculation there was no error but in the epw, i found error like

MPI processes distributed on 1 nodes
Title line not specified: using 'default'.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Error in routine epw_readin (5010):
reading input_epw namelist
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

stopping ...

this types of error is generally occurred when we don't have correct input file but didn't make any modification in the epw.in file.

please suggest me the possible solution.

Thank you and waiting for your kind response.

sponce
Site Admin
Posts: 616
Joined: Wed Jan 13, 2016 7:25 pm
Affiliation: EPFL

Re: how to run epw

Post by sponce »

Hello,

Can you try the superconductivity test in q-6.2.1/test-suite/epw_super/

Those should work as they are automatically tested by the test-farm.

The example sometimes get depreciated (I will update them for the next release).

PS: Note that you might have to download the test-suite from the QE website.

Best,
Samuel
Prof. Samuel Poncé
Chercheur qualifié F.R.S.-FNRS / Professeur UCLouvain
Institute of Condensed Matter and Nanosciences
UCLouvain, Belgium
Web: https://www.samuelponce.com

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