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[Masayoshi Mikami <mmikami@rc.m-kagaku.co.jp>]

Hello,

I came across the following Ph.D thesis (related to "ADF-BAND").
I just thought that it might be interesting to those who are concerned.
So please let me share the information with the forum ML subscribers.
        "Time-dependent density functional theory for periodic systems"
        Freddie Kootstra
        http://www.scm.com/Doc/ft439.pdf

Best wishes,
Masayoshi

On 2004/02/18, at 23:20, Cote Michel wrote:

> Hello Axel,
>
> As far as I know, TDDFT does not quite work for extended systems at 
> present. The problem is in the functional used to get fxc. The 
> implementation in Abinit presently is TDLDA (or TDGGA I think) and 
> those have been shown to have not effect on the Kohn-Sham eigenvalues, 
> so the correction is nil. In short, we have to wait for the 
> development of a good functional.
>
> It will be nice of you to share your results on the supercell of Si 
> but I expect that you will get no change on the value of the energy 
> gap.
>
> Michel
>
> ***************************************************************
>   Michel Cote                          tel: +1 (514) 343-5628
>   Professeur adjoint                   fax: +1 (514) 343-2071
>   Département de physique
>   Université de Montréal
>   C.P. 6128, succ. Centre-ville
>   Montréal (Québec) H3C 3J7          Michel.Cote@umontreal.ca
>   Canada              http://www.phys.umontreal.ca/~michel_cote
> ***************************************************************
>
>
>
>
>
> > -----Message d'origine-----
> > De : avdw@northwestern.edu [mailto:avdw@northwestern.edu]
> > Envoyé : 18 février, 2004 09:07
> > À : forum@abinit.org
> > Objet : [abinit-forum] Time Dependent DFT in extended solids?
> >
> >
> > Hi everyone,
> > is it possible to obtain excitation energies with TDDFT in extended
> > solids with abinit?
> > I undertstand that only single k-point calculations are implemented at
> > this point,
> > but using a supercell can easily take care of that restriction.
> > I am mostly concerned with the requirement of specifying the
> > "center" of
> > the molecule, which is impossible for an extended solid.
> > However, I tested various "boxcenter" values and obtained the
> > same excitations
> > energies in Si, as far as I can tell.
> > So, it looks like as long as I do not need the "oscillator strengths",
> > using a supercell works fine.
> > I am correct in my assumption?
> > Thanks,
> > Axel