[Pw_forum] spilling parameter in Lowdin - how to assign the charge that went into Nirvana ?

[Konstantin Kudin]

 Hi all,

 Revisiting this month old topic, I'd like to ask how easy/difficult
would it be to add the optimization of the atomic basis for the Lowdin
charge evaluation?

 The optimization is described here:
http://dx.doi.org/10.1016/0038-1098(95)00341-X

 With that, one could perhaps even calculate the spread of the atomic
density, and figure out if the atom became larger/smaller as a result
of chemical interaction.

 Thanks!
 Kostya


--- Paolo Giannozzi <giannozz at nest.sns.it> wrote:

> 
> On Mar 24, 2007, at 15:54 , Andrea Ferretti wrote:
> 
> > Lowding orbitals in Quantum-Espresso (at least as far as I know)
> are
> > computed from the atomic reference states from pseudopotential data
> > according to:
> >
> > S_ij = < i | j >      are the overlaps of atomic orbitals i and j
> >
> > lowding orbitals are then obtained as
> > | low_i > =  R_ij  | j >
> >
> > where  R = S^{-1/2}
> >
> > so I think there is no optimization (in the sense of the paper
> above)
> > but maybe I am missing something
> 
> no, you aren't missing anything: the atomic basis is not optimized
> 
> Paolo
> ---
> Paolo Giannozzi, Democritos and University of Udine, Italy
> 
> 
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com