COHSEX stopping without error messages

Concerns issues with computing quasiparticle corrections to the DFT eigenvalues - i.e., the self-energy within the GW approximation (-g n), or considering the Hartree-Fock exchange only (-x)

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elena.mol
Posts: 17
Joined: Mon Oct 04, 2010 10:04 am

Re: COHSEX stopping without error messages

Post by elena.mol » Mon Nov 07, 2011 2:31 pm

Dear all,
i followed Daniele's advice and downloaded the most recent yambo SVN version.
Using this version, my COHSEX runs finish regularly without error messages and without stopping as in the previous cases i mentioned. They also write (as expected for a normal run) "o......" files.


The quasiparticle corrections obtained for my system (big isolated molecule, 1 kpoint.. ) with the SVN version are finite numbers if i use energy cutoffs (FFTGvecs, EXXRLvcs) of 4 or 3 Ry, while i obtain "NaN" corrections if using 2 Ry cutoffs. A COSHEX run on a small test molecule (CH4) instead gives finite corrections already with 2 Ry cutoffs. So it may be a convergence problem..... (?)

So it seems the problem is solved, provided i use appropriate values for the cutoffs
(of course i still have to check if i am already at convergence or not, but this is something standard....)

Thanks again for the suggestions
best
Elena

Elena Molteni
Department of Physics
University of Milan
via Celoria, 16
I-20133, Milan, Italy
and European Theoretical Spectroscopy Facility (ETSF)
http://www.etsf.eu

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