A possibility would be to hack the functional, and gradually “switch on” the TB09 functional starting from PBE: something like FUNCT[alpha] = alpha*TB09 + (1-alpha)PBE, but this, of course, requires some coding … SB
> On 21 May 2020, at 08:46, Paolo Giannozzi <p.gianno...@gmail.com> wrote: > > On Wed, May 20, 2020 at 9:34 PM Michal Krompiec <michal.kromp...@gmail.com > <mailto:michal.kromp...@gmail.com>> wrote: > I changed io_rho_xml.f90 so that if the kinetic energy density file isn't > found, the array is set to 0: > [...] > Now I can start a TB09 calculation from a PBE density, but still my test case > diverges immediately (...) > I would be very grateful for any suggestions. > > unfortunately I haven't any. > > Paolo > > Best, > Michal > > P.S. This is my input file: > &CONTROL > calculation = "scf" > prefix = "sic" > / > > &SYSTEM > a = 4.34800e+00 > ibrav = 1 > ecutwfc = 82 > ecutrho = 328 > nat = 8 > ntyp = 2 > occupations = "fixed" > input_dft='tb09' > / > &ELECTRONS > electron_maxstep = 1000 > conv_thr = 1e-10 > mixing_mode = 'plain' > mixing_beta = 0.4 > startingpot = 'file' > startingwfc = 'file' > diagonalization = 'cg' > / > > K_POINTS automatic > 8 8 8 1 1 1 > > ATOMIC_SPECIES > Si 28.08500 Si.upf > C 12.01060 C.upf > > > ATOMIC_POSITIONS {angstrom} > Si 0.000000 0.000000 0.000000 > Si 0.000000 2.174000 2.174000 > Si 2.174000 0.000000 2.174000 > Si 2.174000 2.174000 0.000000 > C 1.087000 1.087000 1.087000 > C 1.087000 3.261000 3.261000 > C 3.261000 1.087000 3.261000 > C 3.261000 3.261000 1.087000 > > On Fri, 8 May 2020 at 09:39, Paolo Giannozzi <p.gianno...@gmail.com > <mailto:p.gianno...@gmail.com>> wrote: > > > > On Thu, May 7, 2020 at 10:33 PM Michal Krompiec <michal.kromp...@gmail.com > > <mailto:michal.kromp...@gmail.com>> wrote: > > > >> > >> it was suggested to start from a density calculated with a different > >> functional, but when I try to read in PBE density, it complains that it > >> cannot read the kinetic energy file (which obviously cannot be there). > > > > > > this can be easily changed, I think: just disable the check and set the > > kinetic energy density to zero > > > >> > >> Should TPSS or SCAN pseudos work better (and where do I get them from)? > > > > > > I don't think the problem is in the pseudos but in the nasty numerical > > behavior of meta-GGAs. See for instance here: > > https://gitlab.com/QEF/q-e/-/issues/32 > > <https://gitlab.com/QEF/q-e/-/issues/32>. Note that several bugs have been > > fixed in the development version. > > > > Paolo > > > >> Thanks, > >> Michal Krompiec > >> Merck KGaA > >> > >> _______________________________________________ > >> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso > >> <http://www.max-centre.eu/quantum-espresso>) > >> users mailing list users@lists.quantum-espresso.org > >> <mailto:users@lists.quantum-espresso.org> > >> https://lists.quantum-espresso.org/mailman/listinfo/users > >> <https://lists.quantum-espresso.org/mailman/listinfo/users> > > > > > > > > -- > > Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, > > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > > Phone +39-0432-558216, fax +39-0432-558222 > > > > _______________________________________________ > > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso > > <http://www.max-centre.eu/quantum-espresso>) > > users mailing list users@lists.quantum-espresso.org > > <mailto:users@lists.quantum-espresso.org> > > https://lists.quantum-espresso.org/mailman/listinfo/users > > <https://lists.quantum-espresso.org/mailman/listinfo/users> > _______________________________________________ > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso > <http://www.max-centre.eu/quantum-espresso>) > users mailing list users@lists.quantum-espresso.org > <mailto:users@lists.quantum-espresso.org> > https://lists.quantum-espresso.org/mailman/listinfo/users > <https://lists.quantum-espresso.org/mailman/listinfo/users> > > > -- > Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, > Univ. Udine, via delle Scienze 208, 33100 Udine, Italy > Phone +39-0432-558216, fax +39-0432-558222 > > _______________________________________________ > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) > users mailing list users@lists.quantum-espresso.org > https://lists.quantum-espresso.org/mailman/listinfo/users — Stefano Baroni - Trieste — http://stefano.baroni.me <http://stefano.baroni.me/>
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