Wave-vector-dependent Stoner approach to band ferromagnetism in Ni

Recent experimental evidence [W. von der Linden et al., Phys. Rev. Lett. 71, 899 (1993)] that the exchange splitting in Ni follows the temperature dependence of the magnetization and provides strong support for the physical basis of the Stoner model of itinerant ferromagnetism. In this work, augmented plane wave results for paramagnetic and spin-polarized bands (supplemented by a single-parameter shrinking of the band splitting to fit the experimental value available at the symmetry point L-3) are used in a k-dependent, Stoner-like calculation, of the Curie temperature of Ni. The calculated magnetization curve, saturation magnetization, Curie temperature, and specific heat coefficient are in agreement with experiment.