Emine Kucukbenli wrote: > It is clearly stated there that "the non-local contribution due to the > pseudopotential is neglected. Actually the correction to the matrix > element that take into account the non-local part of the Hamiltonian > is not implemented." > So to develop the code for USPP you need to find a way to calculate & > add these corrections, I guess.
it is not sufficient. For norm-conserving PP, there is a nonlocal contribution to the matrix elements <\psi_i| r | \psi_j> (i /= j) that is not accounted for in epsilon.x . This is the meaning of the above statement. For USPP, additional terms have to be added, since only the smooth term of |\psi_i> (the one expanded into plane waves) is available. The correct calculation of matrix elements is actually performed in the phonon code and could be in principle imported into epsilon.f90. P. -- Paolo Giannozzi, Democritos and University of Udine, Italy
