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Nb Pseudopotential
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Flavour of the pseudopotential: Troullier-Martins.
Exchange and correlation functional: GGA (Wu-Cohen).
Relativistic: yes.
Core corrections: yes.
Cutoff radius for the non-linear core corrections: 1.5 bohrs
Valence reference configuration: 4s2 4p6 4d4 4f0
                                 (ionic configuration, net charge +1).
Cutoff radii: 4s 1.60 bohr
              4p 1.50 bohr
              4d 1.50 bohr
              4f 2.00 bohr

