[Pw_forum] spin orbit and custom occupations

Andrea Dal Corso dalcorso at sissa.it
Fri Sep 27 09:07:00 CEST 2013

With spin-orbit coupling states are not eigenstates of S_z,
so one cannot separate spin up and spin down.
However when spin-orbit is small and magnetization is large the states
can be mainly spin up or mainly spin down and you can see this by
calculating the expectation value of \sigma_z (if the magnetization is
along z). This can be done with the band.x program.

HTH,

Andrea

On Thu, 2013-09-26 at 18:33 +0200, Julen Larrucea wrote:
> Thanks Andrea,
>
>
> but this doesn't really solve my problem...
>
>
> I still can't find from example06 how to check the final occupations.
>
> If I use nspin=4, which is supposed to be spin-polarized, unlike in
> the case of nspin=2, I only get a single row of occupations, like this
>
>      occupation numbers
>      1.0000   1.0000   1.0000   1.0000   1.0000   1.0000   1.0000
> 1.0000
>      1.0000   1.0000   1.0000   1.0000   1.0000   1.0001   0.9219
> 0.1150
>     -0.0167  -0.0202   0.0000   0.0000   0.0000   0.0000   0.0000
> 0.0000
>
>
> But which of them are up or down? or, how can I find out whether I
> have a singlet or a triplet in my single isolated atom?
>
>
>
>
>      Julen
>
>
>
>
>
> On Wed, Sep 25, 2013 at 2:31 PM, Andrea Dal Corso <dalcorso at sissa.it>
> wrote:
>         constrained_magnetization='total'
>
>         allows you to fix the magnetization vector. See example06 for
>         more
>         details.
>
>         HTH,
>
>         Andrea
>
>
>
>         On Wed, 2013-09-25 at 11:51 +0200, Julen Larrucea wrote:
>         > Dear colleagues,
>         > Does anybody know how to set precisely the occupations on a
>         spin orbit
>         > calculation (lspinorb=.true.)?
>         >
>         > I have tried to occupations='from_input' but it does not
>         > minority spin line, and constrained- and tot_magnetization
>         do not seem
>         > to work either.
>         >
>         >
>         >
>         >
>         >     Julen
>         > --
>         > Dr. Julen Larrucea
>         > Postdoctoral researcher,
>         > BCCMS, HMI Group, University of Bremen
>         > Phone: +49 421 218 64582
>         > Fax: +49 421 218 64599
>         >  http://www.larrucea.eu
>
>         > _______________________________________________
>         > Pw_forum mailing list
>         > Pw_forum at pwscf.org
>         > http://pwscf.org/mailman/listinfo/pw_forum
>         --
>         Andrea Dal Corso                    Tel. 0039-040-3787428
>         SISSA, Via Bonomea 265              Fax. 0039-040-3787249
>         I-34136 Trieste (Italy)             e-mail: dalcorso at sissa.it
>
>
>         _______________________________________________
>         Pw_forum mailing list
>         Pw_forum at pwscf.org
>         http://pwscf.org/mailman/listinfo/pw_forum
>
>
>
> --
> --
> Dr. Julen Larrucea
> Postdoctoral researcher,
> BCCMS, HMI Group, University of Bremen
> Phone: +49 421 218 64582
> Fax: +49 421 218 64599
>  http://www.larrucea.eu
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
--
Andrea Dal Corso                    Tel. 0039-040-3787428
SISSA, Via Bonomea 265              Fax. 0039-040-3787249
I-34136 Trieste (Italy)             e-mail: dalcorso at sissa.it