Available pseudopotentials:
TPSS (Tao-Perdew-Staroverov-Scuseria) meta-GGA nonlinear core-correction Martins-Troullier
Perdew-Zunger (LDA) exch-corr Bachelet-Hamann-Schlueter and derived
Perdew-Wang 91 gradient-corrected functional nonlinear core-correction Vanderbilt ultrasoft