Hi Lorenzo, I did exactly what you said and I got the same convergence chart on both tests... I'm working with g-alumina and ultrasoft pp... My first convergence test suggested an ecutwfc value between 50Ry-70Ry... Then I used ecutrho = 280Ry for the second test... It means that I can use ecutrho = 4*ecutwfc, right?
[]s Ary Junior On Wed, Sep 30, 2009 at 1:00 PM, Lorenzo Paulatto <paulatto at sissa.it> wrote: > In data 30 settembre 2009 alle ore 17:48:41, udayagiri sai babu > <udayagiri3 at gmail.com> ha scritto: > > > Dear all > > I did convergence tests for chromium. The ecut value i obtained for > > energy converged to 1mRyd is 60Ryd! which i believe is very high for an > > Ultra Soft PP can somebody tell me if i am doing something wrong. Given > > below are my > > sample input file and ecut vs total energy. > > Dear Udayagiri, > what about the cutoff for charge density? > One good procedure to find a nicely converged cutoff is to increase > ecutwfc until it converges than set ecutrho to 4*ecutwfc and reduce > ecutwfc keeping ecutrho fixed. > > Maybe you can fix ecutrho to 240 and see how low you can go with ecutwfc > > best regards > > > -- > Lorenzo Paulatto > SISSA & DEMOCRITOS (Trieste) > phone: +39 040 3787 511 > skype: paulatz > www: http://people.sissa.it/~paulatto/<http://people.sissa.it/%7Epaulatto/> > > *** save italian brains *** > http://saveitalianbrains.wordpress.com/ > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > -- http://lattes.cnpq.br/8221674673413336 -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20090930/8fc5ccc7/attachment.htm
