On Apr 3, 2012, at 6:15 , jia chen wrote: > I am trying to calculate the work function based on CP calculation. > In order to do that, I need to figure out the electrostatic > potential corresponding to cp eigenvalues in real space. I tried PP > post possessing, but the result looks consistent with pwscf, but cp > eigenvalues present a shift. I also tried to print out variable > vpot, but it looks not like electrostatic potential. I hope some > one here has experience dealing with this problem, or some one > knows the origin of eigenvalue shift between cp and pwscf and how > to calculation that.
I am not sure what "potential" exactly is actually contained in the potential file written by CP. I am quite sure instead about the origin and size of the shift between Kohn-Sham eigenvalues printed by CP and by PWscf. In recent CP versions, look for "Delta V(G=0)" in the output: this is the difference between the potential at G=0 for CP and for PWscf. Explanations here: http://www.fisica.uniud.it/~giannozz/public/ewald.pdf P. --- Paolo Giannozzi, Dept of Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
