Dear Izaak, Looking at your input file, a few things to try out came to mind:
1 - Did you try to integrate using more k points? Experiment with, say, 3x3x3 K points and see if anything changes. 2 - Try the calculation with ecutrho = 360, see if anything changes. Hope it might help. Giovani M. Faccin UFMS - Brazil 2011/5/3 Izaak Williamson <izaakw89 at yahoo.com> > Dear all, > > I am trying to calculate the cohesive energy of the N2 molecule using the > attached input file (relax.in) and am getting a value of -16.57 eV. I use > DFT with GGA and the pseudo-potential N.pbe-rrkjus.UPF. Other work [Fuchs > et. al., Phys. Rev. B 65, (2002)245212] has performed similar calculations > and obtained values ~10.5 eV. They even list an experimental value of 9.76 > eV. Why is my value so much higher? Is there anything in my input file that > could be giving inaccurate results? Is it my pseudo-potential that is > causing this problem? > > Thanks for any help. > > -- > Izaak Williamson > Research Assistant > Physics Department > Boise State University > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- Giovani -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110503/3f45835a/attachment.htm
