[Pw_forum] van der waals force

[Axel Kohlmeyer]

On Tue, 2009-05-19 at 11:09 -0400, Nicola Marzari wrote:
> Axel Kohlmeyer wrote:
> > 2009/5/19 Mehrnaz Anvari <anvari_meh at physics.iust.ac.ir>:
> >> Dear axel
> >> Thanks a lot because of your answer. As you said I am trying to understand
> >> the DFT-D method. Now I have another question about difference between
> >> pseudo potential code & full one. Is the latter suitable for dispersion
> > 
> > dear mehrnaz,
> > 
> > this question can be answered with common sense. there are
> > two points to consider:
> > a) pseudopotentials integrate out core electrons. can you imagine
> >    those to contribute to dispersion interactions?
> 
> 
> I couldn't, but it was pointed out that Pekka Pykko has done a lot
> of work discussing the relevance of vdW interactions between filled
> d-shells (e.g. in silver compounds).

interesting point. i would argue that in this case a pseudopotential
that does not include those d-states in the valence would be 
inadequate to begin with, but - of course - this is a bit of a 
circular argument... ;)

cheers,
   axel.


> 
> 			nicola
> 
> 

-- 
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
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