Thanks a lot for all the help! Now I have a much better understanding on this issue.
Best, -Peter ******************************************** Peter Winey, Ph.D., DuPont peterwiney at gmail.com ******************************************** On 7/22/08, Stefano de Gironcoli <degironc at sissa.it> wrote: > > Dear Peter Winey, > > I think the problem with the elf + US is that the local kinetic energy in > the core region is not well defined. > In the PAW formalism the all-eletron wave functions can be reconstructed > and from them the kinetic energy density could be calculated hence this is a > well defined object, but in the US case you only have the augmentation > charges that are insufficient to define it. > In practice, I guess, the choice of NOT adding any augmentation kinetic > energy is made which is somehow unsatisfactory (hence the "not fully > implemented" cavet).. > Notice that even for NC pseudopotential the elf is unphisical in the core > region > since the core contribution should in principle also be considered, which > is not.... not to mentin that the pseudowfc in the core are wrong... > So in conlusion I think that in general one should trust the calculated elf > in the interstitial region but NOT in the core region (both for US and NC), > only PAW, or some PAW-like wfc reconstruction (including core contributions) > could give good results in the regions. > > stefan > -- -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20080722/623dfd3b/attachment.htm
