Dear Yuki-san,
prompted by your question, and thanks to kind help from David O'Regan, I've written a short tutorial on this here (see oxidation states): http://theossrv1.epfl.ch/Main/Tutorials In a nutshell, it's very doable, albeit with some scripting to streamline the extra calculations needed. nicola On 11/06/2014 06:31, ???? wrote: > Dear PWSCF users. > > I'm now try to fixed the valence of one atom in the cell. > > For example, how we impose one of the Nb atom as (+4) valence > > (one electron is localized in Nb atom Nb(+5) is ideal condition ) > > in the crystal. > > I tried to use constrained_magnetization = 'atomic' > > with statring_magnetization like below, > > (Here atom index 2 is Nb atom which I set as valence (+4, one electron > > localized in Nb atom, 3 is Nb atom with ideal +5 valence ) > > starting_magnetization(1) = 0.0 > starting_magnetization(2) = 1.0 > starting_magnetization(3) = 0.0 > starting_magnetization(4) = 0.0 > starting_magnetization(5) = 0.0 > lda_plus_u =.TRUE. > lda_plus_u_kind = 0 > Hubbard_U(2)=4.0 > Hubbard_U(3)=4.0 > tot_charge = -1.0 > tot_magnetization = 1.0 > constrained_magnetization = 'atomic' > lambda = 1.0 > > But, the results was some of Nb atoms has a little excess electron (, > but smaller than one ), and I couldn't get +4 Nb which I aimed to > make. > > How to treat to impose the localized electron in one of the atoms > > in crystals. > > If I can get reply, I'm very happy. > > Sincerely, > > Yukihiro Okuno. > > -- > ? > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- ---------------------------------------------------------------------- Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL
