Spin-orbit coupling, Fermi surface, and optical conductivity of ferromagnetic iron

A previous self-consistent linear-combination-of-atomic-orbitals calculation of energy bands in iron has been extended through the inclusion of spin-orbit coupling. The exchange interaction is incorporated according to the Xα method. The Fermi surface is described in detail and compared with the results of measurements of the de Haas-van Alphen effect, and of magnetoresistance anisotropy. The interband contribution to the optical-conductivity tensor was computed using matrix elements determined from wave functions including spin-orbit coupling. Both diagonal and off-diagonal elements of this tensor have been obtained.