Band structure and related properties of bcc niobium

We report self-consistent, all-electron calculations of the band structure of paramagnetic bcc niobium. Density-functional theory and the linear combination of Gaussian orbitals method were employed. Results are presented and discussed in the light of the existing theoretical and experimental data for the energy bands, density of states, Fermi surface, optical conductivity, x-ray form factors, and Compton profile. In addition, spin-polarized band-structure calculations were carried out to investigate a possible magnetically ordered state for large values of the lattice constant. A composite transition from a nonmagnetic to a low-spin ferromagnetic state and from a low to a high-spin state was found.