"besides the statement: be careful with the energy parameter (very fine E-search in case.in1)" N.B., one does not need a fine search in the more recent Wien2k, only in the older versions.
I seem to remember that GMax 20 mainly cancels out for LDA/GGA -- I would always use it (or more) for a meta GGA. _____ Professor Laurence Marks "Research is to see what everybody else has seen, and to think what nobody else has thought", Albert Szent-Gyorgi www.numis.northwestern.edu On Nov 13, 2017 2:00 PM, "Peter Blaha" <pbl...@theochem.tuwien.ac.at> wrote: > 1- Computing the atomic energies of atoms like N and P in an FCC cell is > ok, however for O atom the high symmetry of the FCC cell results in 1/3 > occupancies (for the 4th p electron of O) in the spin down case. Only > using a lower symmetry cell (orthorhombic) for O atom eliminates this issue. This is true, however, for O this is a very small (negligible) energy difference. It is a bit more important (also to help convergence) for transition metals or even lanthanides. > 2- For very small RMTs (e.g. 1.1 for O) one needs a large value of Gmax > (~20). Again true. GMAX for small spheres has some effect on E-tot. I have not cross checked if this truncation cancels out in the energy differences. > Using RMT = 1.1 for O in a compound will require one to use too small > RMTs for large atoms. For example if we use RMT = 1.1 for O in compounds > like SnO2, this will require one to use an RMT ~ 1.6 for Sn (RMTs > difference should not be > 30 %). This means that the ecut should be set > < -9.8 Ry which includes the 4s electrons to valence states. What are > the consequences? Without test: I would "break" my own rules and set the Sn sphere still to 2.0 or 2.2 (such that no core leakage occurs at ecut=-6). I would not expect ghostbands coming up. This rule usually applies to cases where one atom could have very large RMT (2.5 or even larger) and probably converges rapidly (eg. alkali(earth) atoms in TM perovskites, ...) But in principle there is nothing to say against Sn 4s as valence, besides the statement: be careful with the energy parameter (very fine E-search in case.in1) and make sure that RKmax is sufficient for such localized states. > > Best Regards, > > Alay > > > > _______________________________________________ > Wien mailing list > Wien@zeus.theochem.tuwien.ac.at > https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus. theochem.tuwien.ac.at_mailman_listinfo_wien&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=zF60VSvgkhXPgAFuKbK1JGP3NGj05D 16OuNwQfn_Biw&e= > SEARCH the MAILING-LIST at: https://urldefense.proofpoint. com/v2/url?u=http-3A__www.mail-2Darchive.com_wien- 40zeus.theochem.tuwien.ac.at_index.html&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=HPtZ_3ky-3VP12W- LspS4XUBxVKHyqea_oR9uKgVGyE&e= > -- -------------------------------------------------------------------------- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.at WIEN2k: https://urldefense.proofpoint. com/v2/url?u=http-3A__www.wien2k.at&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=0xx31L8x_pX0tSE6QCwnu0ieVyBv4AN1- QfKUvUvjnk&e= WWW: https://urldefense.proofpoint.com/v2/url?u=http-3A__www.imc. tuwien.ac.at_tc-5Fblaha-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D- 2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D- 2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D- 2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D-2D&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=GjL51v86wzTeoP28vT7izbE- GVvMlSxptO2qD8t58To&e= _______________________________________________ Wien mailing list Wien@zeus.theochem.tuwien.ac.at https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus. theochem.tuwien.ac.at_mailman_listinfo_wien&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=zF60VSvgkhXPgAFuKbK1JGP3NGj05D 16OuNwQfn_Biw&e= SEARCH the MAILING-LIST at: https://urldefense.proofpoint. com/v2/url?u=http-3A__www.mail-2Darchive.com_wien- 40zeus.theochem.tuwien.ac.at_index.html&d=DwICAg&c= yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_ T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=AQ_ 8qeipj47Nvnx3rH6ZWBnmVNH79mLnft7Udb_swzA&s=HPtZ_3ky-3VP12W- LspS4XUBxVKHyqea_oR9uKgVGyE&e=
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