Bug report in p2y

Come here to discuss issues with using the p2y converter from PWscf to Yambo, how to best run PWscf , link with the IOTK library, and so on.

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Posts: 12
Joined: Tue Oct 04, 2011 9:52 am

Bug report in p2y

Post by sponce » Mon Jan 29, 2018 12:35 pm


This is simply a bug report. I'm using Yambo 4.2.0 and q-e-6.0.

It seems that p2y cannot cope with imposing the k-point grid in the nscf step:
nosym = .true.
K_POINTS crystal
0.00000000 0.00000000 0.00000000 1.562500e-02
0.00000000 0.00000000 0.25000000 1.562500e-02
0.00000000 0.00000000 0.50000000 1.562500e-02
0.00000000 0.00000000 0.75000000 1.562500e-02
0.00000000 0.25000000 0.00000000 1.562500e-02
0.00000000 0.25000000 0.25000000 1.562500e-02
0.00000000 0.25000000 0.50000000 1.562500e-02
0.00000000 0.25000000 0.75000000 1.562500e-02
0.00000000 0.50000000 0.00000000 1.562500e-02
0.00000000 0.50000000 0.25000000 1.562500e-02
0.00000000 0.50000000 0.50000000 1.562500e-02
Indeed, if you do that in QE, it will produce a "charge-density.dat" file that does NOT have G-VECTORS. Also the associated gvector.dat is not created. I believe this is intended in QE.

However in interfaces/p2y/qexml.F the code is looking for CALL iotk_scan_begin( iunit, "G-VECTORS", IERR=ierr ) and therefore crash.

It does work if you using

Code: Select all

K_POINTS {automatic}
 4 4 4 0 0 0
instead in the nscf step.

Samuel Poncé
Department of Materials, University of Oxford

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Daniele Varsano
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Re: Bug report in p2y

Post by Daniele Varsano » Mon Jan 29, 2018 12:57 pm

Dear Samuel,
there should a way to fix this within QE.
the wf_collect flag set as .true. in the nscf input should fix the problem.
In case this does not work can you upload th scf/nscf/psp input files?


Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale

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Joined: Fri Jan 31, 2014 11:13 am

Re: Bug report in p2y

Post by andrea.ferretti » Mon Jan 29, 2018 3:07 pm

also note that

Code: Select all

needs to be there in nscf runs anyway in order to run p2y

Andrea Ferretti, PhD
CNR-NANO-S3 and MaX Centre
via Campi 213/A, 41125, Modena, Italy
Tel: +39 059 2055322; Skype: andrea_ferretti
URL: http://www.nano.cnr.it

Posts: 12
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Re: Bug report in p2y

Post by sponce » Mon Jan 29, 2018 6:41 pm

Dear Andrea and Daniele,

I do confirm that I did not include the wf_collect=.true. flag.
It does indeed work with the flag.

Thank you !
Samuel Poncé
Department of Materials, University of Oxford

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