Dear all, I do not understand why the two highlighted places in the attached DFPT review paper are correct.
I repeat my questions here: 1. Why the contributions from valence bands cancel each other? 2. Why the left side of Eq.25 has a null eigenvalue? Thank you! Andy -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20121024/86586156/attachment-0001.html -------------- next part -------------- A non-text attachment was scrubbed... Name: RMP_questions.pdf Type: application/pdf Size: 56377 bytes Desc: not available Url : http://pwscf.org/pipermail/pw_forum/attachments/20121024/86586156/attachment-0001.pdf
