Dear Monhish, thanks again for your answer. So, if I am understanding correctly I should just perform a scf run with a dense k-point grid and then go on with the DOS using projwfc.x or dos.x, that's right? I was performing a nscf run after the scf one because I was following the tutorial:
http://www.fisica.uniud.it/~giannozz/QE-Tutorial/ *Post-processing and data analysis* (slides <http://www.fisica.uniud.it/%7Egiannozz/QE-Tutorial/tutorial_postproc.pdf>, examples <http://www.fisica.uniud.it/%7Egiannozz/QE-Tutorial/examples_postproc.tgz>) Regards, Valentina Il 04/09/2013 04:20 PM, mohnish pandey ha scritto:** > Dear Valentina, > > You can do the calculations with the SCF run in HSE/PBE0, that > shouldn't be a problem. And why do you need nscf calculation anyway to > do the DOS calculation. 'nscf' calculation is needed when you are > interested in band-structure where you use the ground state charge > density for interpolation along certain directions. Your scf > calculations will won't have any problem in calculation the DOS. Hope > it helps :) > > > On Tue, Apr 9, 2013 at 3:10 PM, "Valentina Dellac? C.R.F. S.C.p.A." > <valentina.dellaca at tirocinanti.crf.it > <mailto:valentina.dellaca at tirocinanti.crf.it>> wrote: > > Dear Arles, > thanks for your answer. My doubts are about the employment of the > projwfc.x, post processing tool, when using hybrid functional, > since the README of the hybrid functional tutorial says that one > gets into troubles when performing non-scf calculations. At the > moment I see the way to proceed if I wish to plot the band > structure from the log file of the scf run, but i do not know how > to get informations about the dos from such file, since it (as far > as I understand) seems to be the only run i can perform when > employing hybrid functionals. Do you know how to get informations > about the dos from the .log of a scf run? > Thank you!!! > Valentina > > Il 04/09/2013 02:24 PM, Arles V. Gil Rebaza ha scritto: >> Dear Valentina, >> Yes, projwfc.x is a postprocessing tool like dos.x, whether you >> want to get only the density of state, "dos.x" is enough, whereas >> "projwfc.x" you can obtain DOS, projected DOS (PDOS) and the >> magnetic moment per atom too. >> http://www.quantum-espresso.org/?page_id=876 >> >> Best >> >> PhD Arles V. Gil Rebaza >> Instituto de F?sica de La Plata >> Argentina >> >> >> 2013/4/9 "Valentina Dellac? C.R.F. S.C.p.A." >> <valentina.dellaca at tirocinanti.crf.it >> <mailto:valentina.dellaca at tirocinanti.crf.it>> >> >> Dear Mohnish, >> thanks for you answer. I will follow your suggestion and try >> also HSE, with a coarser k-point mesh, (indeed with PBE0 the >> computation time is quiet large), and I did not know about >> projwfc.x. >> I have a further question concerning the DOS. If I wish to >> know about the DOS of my system, which uses the hybrid >> functional implementation, am I able to use the projwfc.x? >> Is'n it a postprocessing tool? >> Thanks, >> regards, >> Valentina >> >> Il 04/09/2013 11:18 AM, mohnish pandey ha scritto: >>> Hi, >>> >>> As far as I can understand there is no rule. It depends how >>> fine you want to represent your Fock operator. Normally >>> calculations of the Fock exchange in expensive, so its not >>> affordable to do very fine grid calculations So I suggest >>> you start with low nqx(1, 2, 3) and increase it >>> systematically. Increasing it will give you better results( >>> I mean converged results, not necessarily close to >>> experiments). >>> >>> Just an advice, PBE0 needs much more high density k-point >>> mesh for the convergence of Fock exchange since it's a long >>> range interaction. So you have to do calculations with high >>> density of k-points. But if you use HSE instead of PBE0 you >>> get away with coarser k-point mesh since it involves >>> screened exchange interaction which converges much faster >>> than bare Coulomb exchange as in PBE0. Regarding to the DOS >>> plot you will find a nice tutorial on Heither's website, I >>> am pasting the link >>> >>> http://www.stanford.edu/~hkulik/www/Tutorials/Entries/2012/1/24_Population_analysis_and_PDOS.html >>> >>> <http://www.stanford.edu/%7Ehkulik/www/Tutorials/Entries/2012/1/24_Population_analysis_and_PDOS.html> >>> >>> >>> On Tue, Apr 9, 2013 at 10:05 AM, "Valentina Dellac? C.R.F. >>> S.C.p.A." <valentina.dellaca at tirocinanti.crf.it >>> <mailto:valentina.dellaca at tirocinanti.crf.it>> wrote: >>> >>> Hi, >>> I am a Quantum Espresso beginner user, and I am >>> simulating the Ta2O5 structure, with the employment of >>> the hybrid functional PBE0. I have some questions : >>> >>> - if I choose a k-point grid not in automatic, how >>> should I pick the nqx1,2,3? Is there a rule? >>> - when one wishes to have informations (ex. plot) about >>> the density of states from the scf run, how should I >>> proceed? >>> >>> Thank you, >>> regards >>> Valentina >>>> >>>> -- >>> >>> >>> -- >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> Pw_forum at pwscf.org <mailto:Pw_forum at pwscf.org> >>> http://pwscf.org/mailman/listinfo/pw_forum >>> >>> >>> >>> >>> -- >>> Regards, >>> MOHNISH, >>> ----------------------------------------------------------------- >>> Mohnish Pandey, >>> PhD Student, >>> Center for Atomic Scale Materials Design, >>> Department of Physics, >>> Technical University of Denmark >>> ----------------------------------------------------------------- >> >> >> -- >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org <mailto:Pw_forum at pwscf.org> >> http://pwscf.org/mailman/listinfo/pw_forum >> >> >> >> >> -- >> ###---------> Arles V. <---------### > > > -- > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org <mailto:Pw_forum at pwscf.org> > http://pwscf.org/mailman/listinfo/pw_forum > > > > > -- > Regards, > MOHNISH, > ----------------------------------------------------------------- > Mohnish Pandey, > PhD Student, > Center for Atomic Scale Materials Design, > Department of Physics, > Technical University of Denmark > ----------------------------------------------------------------- -- -------------- next part -------------- An HTML attachment was scrubbed... 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