Hi Duy, Thanks. I see it in the output, but I was not sure how the ecutrho is set for different PPs. If only one ecutrho in set in one calculation, it is not a good idea to use a mixture of PPs, since then if ecutrho is set to be N*ecutwfc, the same value is used for NC PP.
Vi ________________________________ From: Duy Le <[email protected]> To: PWSCF Forum <pw_forum at pwscf.org> Sent: Tue, May 31, 2011 10:29:36 AM Subject: Re: [Pw_forum] Using mixture of pseudo potential On Tue, May 31, 2011 at 1:11 PM, Vi Vo <vovi47 at yahoo.com> wrote: > Hi Pine, > > Thank you. Yes, I know that I have to do different tests for ecutrho and > ecutwfc, but my questions are different. I would like to know what is the > default setting for ecutrho the code would assume. I restate my question as > follows: > > If I forgot to specify the ecutrho, what default value of ecutrho would the > code assume for US PP? (I guess it still uses the default > ecutrho=4*ecutwfc). > > On the other hand, assuming I set the ecutrho=9*ecutwfc, does then the same > value of ecutrho=8*ecutwfc also apply to NC PP, or does the value of > ecutrho=4*ecutwfc will be used for NC PP. If there is nothing changed, according to the QE manual, the default factor of 4 does not depend on the type of potential. Also, there is only one ecutrho in a single calculation, and it is written in the output (most of parameters can be found in the output). > > Thank you, > -------------------------------------------------- Duy Le PhD Student Department of Physics University of Central Florida. "Men don't need hand to do things" > Vi > > > ________________________________ > From: lucking-pine <songsong19840614 at gmail.com> > To: PWSCF Forum <pw_forum at pwscf.org> > Sent: Mon, May 30, 2011 9:35:59 PM > Subject: Re: [Pw_forum] Using mixture of pseudo potential > > Hi, > In my way,I usually test ecutrho = X*ecutwfc using scf or relax.I look the > result of total energy or enthalpy. > Such as: > 1.ecutwfc=47 ecutrho=400, total energy= -290.983 > 2.ecutwfc=47 ecutrho=380, total energy= -290.993 > So,I thought '2' is better than '1'. > > Bests, > Pine. > 2011/5/31 Vi Vo <vovi47 at yahoo.com> >> >> Dear All, >> >> In my calculation, I used a mixture of pseudo potentials, ie. >> norm-conserving pp (NC pp) for one element and ultrasoft pp (US pp) for >> another. If I don't specify ecutrho in the input, what will be the default >> value for ecutrho for the ultrasoft pp. I know that for NC pp, ecutrho = >> 4*ecutwfc, but I do not know if the same value is used for US pp. On the >> other hand, if I specify ecutrho = 8*ecutwfc, then does the same value apply >> to the NC pp. >> >> Thank you very much, >> >> Vi >> University of Houston >> >> >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://www.democritos.it/mailman/listinfo/pw_forum >> > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > _______________________________________________ Pw_forum mailing list Pw_forum at pwscf.org http://www.democritos.it/mailman/listinfo/pw_forum -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110531/b68880aa/attachment.htm
