[Pw_forum] Relationship between pseudo-charge and wave function

[Paolo Giannozzi]

Hi

> I used "normal" (pw.x) code and ultrasoft PP in my calculation [...]
> However, I think it is meaningful to figure out gamma point
> wavefunction with ultrasoft PPs,too.

- you can plot |psi(r)|^2 for any wavefunction at any k-point,
  using the appropriate options of program pp.x. It's a little
  bit clumsy but it is already implemented.
  I am not sure whether program pp.x can correctly plot 
  wavefunctions produced by codes using only Gamma point
  (having half of the G components). I am afraid it is not working
  now but it will sooner or later (any volunteers?)

- BUT: what you get is just the soft part of the wavefunction.
  In the ultrasoft PP method, there is no "complete" wavefunction,
  just the soft part. A "real", normalized, all-electron wavefunction, 
  can be obtained by applying a non-trivial procedure in the PAW
  style: see for instance J. Chem. Phys. 115, 5791 (2001). Such
  procedure is already implemented and it will be added to the 
  distribution ASAFSIW (= As Soon As Francesco Says It Works,
  Francesco being the guy who wrote the code ... he reads this
  mailing list ... ). 

Does this answer your question?

Paolo


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Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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