A direct space expansion for the local electronic density of states in amorphous metals

Abstract

A Green function formalism is developed in the muffin-tin approximation to calculate the local electronic densities in structurally disordered metals. The local atomic arrangement and also the long-range distribution of the atomic scattering centres are treated on an equal footing by dividing the coordinate space into three regions. In the first region, in the immediate neighbourhood of the central space into three regions. In the first region, in the immediate neighbourhood of the central atom, the further atoms are treated individually, as in a cluster. Outside the cluster, the second region, the atomic distribution is represented by the pair distribution function. The nearly constant tail of this function defines the third region. The local density of states is calculated for different atomic arrangements inside the cluster, and the results are then averaged for different clusters. By applying the method to iron, a single-peaked averaged density of states curve was obtained which is somewhat shifted to lower energies.