Self-consistent pseudopotential calculations for the ideal (001) surface of Nb

A nonlocal self-consistent pseudopotential scheme is employed to calculate the electronic structure of the ideal (001) surface of Nb. Charge densities, electronic local density of states, and the two-dimensional band structure for the surface are presented and discussed. Prominent surface bands and surface resonances are identified and analyzed throughout the two-dimensional Brillouin zone. The projected Nb bulk band structure on the (001) surface is also obtained. Surface states of different angular momentum character are found to exist over a wide range of energies and over different portions of the two-dimensional Brillouin zone. Our calculations predict strong surface features in the density of states in the range 0-2 eV above the Fermi energy.