The ABINIT Users Mailing List ( CLOSED )

[Bernard Amadon <bernard.amadon@cea.fr>]

In fact, as atompaw generates LDA (PW) or GGA (PBE) atomic datasets, I 
think that at least
ixc=7 (PW) and ixc=11 (PBE) have worked since the beginning. Maybe the 
documentation was not sufficiently
explicit on this point.
But to my mind, any value of ixc should work as far as it is compatible 
with nspden=2. If you
have an example of any problem with a specific value if ixc, i would be 
interested to know !

Best regards
Bernard


Josef Zwanziger a écrit :
> Did the ixc issue change? At least in some versions, the ixc variable had to 
> be set to a fairly limited set of possibilities for LDA+U calculations, has 
> that restriction been lifted?
>
> Joe
>
> On Tuesday 27 May 2008 09:32, Bernard Amadon wrote:
>   
> > Hello,
> >
> > To complete the answer, you can find related information in variable
> > usepawu
> > (http://www.abinit.org/Infos_v5.5/input_variables/varpaw.html#usepawu)
> > and in the file  doc/users/HowtodoLDA+U.txt.
> > I would also say, that in principle ixc should not be given in the input
> > as it is supplied in the (PAW) atomic data.
> > In the current implementation in Abinit, both LSDA+U and GGA+U
> > calculations can be carried out:
> > you just have to use LDA or GGA atomic data.
> >
> > Best
> > Bernard Amadon
> >
> > Josef Zwanziger a écrit :
> >     
> > > Hi,
> > > I have found the following combination to work quite well:
> > > 1) Use PAW, and in particular use atompaw to make your PAW data sets (I
> > > had been using USPP for a long time, but I switched--atompaw is much
> > > easier and gives very good results).
> > > 2) In your input, use:
> > >
> > > usepawu 1
> > > lpawu ... (here -1 for the atom types without U+J, and L for the angular
> > > momentum of the atom types to be treated with U and J)
> > > upawu : value of U for each atom type (irrelevant for the atoms in lpawu
> > > that are not being treated)
> > > jpawu: value of J for each atom type (also irrelevant for atoms not being
> > > treated)
> > > nsppol 1 or 2 depending on your system
> > > nspden 2 (required for LDA+U in abinit)
> > > ixc 1 (fairly limited set of ixc's available for LDA+U calcs, see
> > > documentation)
> > > spinat ... (use this to break spin symmetry if desired)
> > >
> > > good luck--
> > >
> > > On Tuesday 27 May 2008 06:52, Anurag Chaudhry wrote:
> > >       
> > > > Hello everyone,
> > > >
> > > > Few days back I saw a couple of mails about LDA+U calculations with
> > > > Abinit. I would like to do LSDA+U calculations.  can anyone suggest how
> > > > to setup such a calculation and what pseudopotentials to use ?
> > > >
> > > > thanks and regards,
> > > > Anurag
> > > >
> > > >
> > > >
> > > >       __________________________________________________________
> > > > Sent from Yahoo! Mail.
> > > > A Smarter Email http://uk.docs.yahoo.com/nowyoucan.html
> > > > This email was Anti Virus checked by Astaro Security Gateway.
> > > > http://www.astaro.com
> > > >         
> > This email was Anti Virus checked by Astaro Security Gateway.
> > http://www.astaro.com
> >     
>
>