Dear Nicola, Thanks very much for this clarification and information, it is a massive help.
Kind Regards Zarah On Wed, Apr 16, 2014 at 6:27 PM, Nicola Marzari <nicola.marzari at epfl.ch>wrote: > On 16/04/2014 11:29, Zarah Baiyee wrote: > > Dear all, > > > > I am studying a BaFeO3 perovskite structure, and I am struggling with > > the convergence, primarily the Ecut WFC convergence. > > > > So far I have used a variety of PPs for this structure, yet cannot get a > > sensible convergence for the Ecut Wfc, please see my convergence data > > below: > > > > Dear Zarah, > > > 1) you do not check cutoff convergence on the total energy, > but on its derivtives: forces for a distorted configuration, > lattice parameters, bulk moduli... E.g. you want an eq. lattice > parameter converged to better than .1 a.u, a bulk modulus converged > to better than 3-4%, and phonons converged to better than 1%. > > 2) for pseudopotentials, the defaults you should probably use are the > http://qe-forge.org/gf/project/pslibrary/ (we keep a compiled version > of all the pseudos here http://theossrv1.epfl.ch/Main/Pseudopotentials) > or the GBRV high-throghput library http://www.physics.rutgers.edu/gbrv/ > (just be careful that this latter might have elements with very large > numbers of semicore electrons - listed here in a very cool manner: > http://theospc12.epfl.ch/GBRV_map/css3d_periodictable_GBRV.html ) > > > nicola > > > ---------------------------------------------------------------------- > Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20140416/8aa3270c/attachment.html
