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["Anglade Pierre-Matthieu" <anglade@gmail.com>]

Since you want a ground state description of your system you have to
round occupation numbers to nearest int in case you have metal like
occupations.

On Mon, May 5, 2008 at 3:18 PM, Anurag Chaudhry
<anuragchaudhry@yahoo.co.uk> wrote:
>
>
> Hi,
>
> Thanks for your reply.
>
> I have tried specifying the occupation by hand (same as what you referred to
> as occopt 0) for an inorganic insulator doped with Cerium (Ce 3+).  In Ce 3+
> we have only one 4f electron so I specified occopt 0 with LDA to get the
> excited state (no spin polarization in this case).
>
> but with other lathanide series elements like Eu2+ I need spin polarization
> and with that I am not sure how to do a constrainted LSDA since for the
> ground state Abinit returns occupation states like 0.85 ... near the fermi
> level.  how to take  these fractional numbers and get the excited state ?
>
>
>
> as an example this is what I get when I do spin polarized calculations for
> the occupation
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>               1.000000  1.000000  1.000000  0.999999  0.999999  0.999999
>               0.999999  0.999999  0.999999  0.999999  0.999999  0.999998
>               0.999998  0.999998  0.999998  0.999996  0.999996  0.999996
>               0.999995  0.999987  0.999987  0..999987  0.999987  0.999979
>               0.999978  0.999978  0.999977  0.999950  0.999948  0.999946
>               0.999946  0.999944  0.999943  0.999942  0.999940  0.999819
>               0.999817  0.999812  0.999806  0.999753  0.999751  0.999745
>               0.999736  0.002378  0.002313  0.002126  0.001895  0.000624
>               0.000603  0.000546  0.000445  0.000139  0.000137  0.000134
>               .........
>
> and for another system with Ce3+ I get occupation states as
>               1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>                1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>                1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>                1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>                1.000000  1.000000  1.000000  1.000000  1.000000  1.000000
>                1..000000  1.000000  1.000000  1.000000  1.000000  1..000000
>               0.000000  0.000000  0.000000  0.000000  0.000000  0.000000
>               0.000000  0.000000  0.000000  0.000000  0.000000  0.000000
>               0.000000  0.000000  0.000000  0.000000  0.000000  0.000000
>
> thanks,
> Anurag
>
> ----- Original Message ----
> From: Anglade Pierre-Matthieu <anglade@gmail.com>
> To: forum@abinit.org
> Sent: Sunday, 4 May, 2008 11:56:22 PM
> Subject: Re: [abinit-forum] constrainted LSDA with Abinit
>
> Hello,
>
> I think it is possible : have you tried to use "occopt 0" and specify
> occupation numbers by hand ("occ") in your input file ?
>
> regards
>
> PMA
>
> On Mon, May 5, 2008 at 6:04 AM, Anurag Chaudhry
> <anuragchaudhry@yahoo.co.uk> wrote:
> >
> > Hello,
> >
> > I would like to know if it is possible to do constrained LSDA calculation
> > with the possibility to explicitly specify the occupation of an excited
> > state.  For a ground state calculation with spin polarization Abinit gives
> > non-integer band occupation for the two spins so I am not sure how to
> > specify the occupation of the excited state.
> >
> > Thank you very much for your time and help.  I am still learning so please
> > pardon me if my question is not clear, I will try to formulate it again.
> >
> > regards,
> > Anurag
> >
> >  ________________________________
> >  Sent from Yahoo! Mail.
> >  A Smarter Email.
>
>
>
> --
> Pierre-Matthieu Anglade
>
>
>  ________________________________
>  Sent from Yahoo! Mail.
>  A Smarter Email.



-- 
Pierre-Matthieu Anglade