The electronic structure of transition metal Laves phases

Abstract

The problem of understanding AB2 transition metal alloy structural trends within the three Laves phases is approached by considering a common-band model alloy. Tight-binding d band densities of states are calculated for the three phases by the recursion method of Haydock, Heine and Kelly (1972). The three total densities of states are very similar, highly peaked structures. The A site local densities of states show a division into bonding and antibonding states. Cohesive energies are computed and it is found that their differences undergo a cyclic variation across the band, which is related to the moments of the densities of states, and hence to the layer stacking of the structures.