I'm using the Teter's extended norm-conserving PP (pspxc=1) and the T-M PPs (pspxc=2) for response function calculations. Certainly I got WARNINGs complaining that I should change my PPs for the ixc consistency. In the BASIC variables, it had been mentioned that "the choices ixc=1, 2, 3 and 7 are fits to the same data, from Ceperley-Alder, and are rather similar, at least for spin-unpolarized systems." So my question is is it safe to ignore these WARNINGs?
Thank you very much!L. Xie