Available pseudopotentials:

Nb.pz-sp-van.UPF   (details)

	 Perdew-Zunger (LDA) exch-corr
	 semicore state s in valence
	 semicore state p in valence
	 Vanderbilt ultrasoft

Nb.pbe-nsp-van.UPF   (details)

	 Perdew-Burke-Ernzerhof (PBE) exch-corr
	 nonlinear core-correction
	 semicore state s in valence
	 semicore state p in valence
	 Vanderbilt ultrasoft

Nb.pw91-nsp-van.UPF   (details)

	 Perdew-Wang 91 gradient-corrected functional
	 nonlinear core-correction
	 semicore state s in valence
	 semicore state p in valence
	 Vanderbilt ultrasoft