Hybridization in amorphous metals

Abstract

We have investigated the effects of s-d hybridization on the electronics states in amorphous or liquid transition metals. First, using computer simulations and a tight-binding model we have compared the effects of hybridization on the density of states in the amorphous and crystalline states. Somewhat surprisingly we find that the densities of states do not differ by very much in the two situations. Secondly we have used a type of perturbation theory to investigate how free electrons are perturbed by hybridization with d-atates. We find that a modified band can persist through the d-atates and that the ‘ E(k) curve ’ can be S-shaped. The lifetimes of these states are sufficiently long to suggest that negative values of dE/dk could explain positive Hall coefficients observed in many amorphous and liquid alloys of transition elements. This phenomenon is very similar to anomalous dispersion in optics.