Self-Consistent Cluster Theory for Electronic Structure of Systems with Local Orders. I. Formulation

Abstract

A method for calculating the electronic density of states of the system with local order is presented. For the system, we set up a model of cluster of atoms embedded in the effective medium. The local order is taken into account by the atomic configuration in a cluster. The potential due to the surrounding medium is assumed to be energy-dependent complex constant. Value of the potential is determined self-consistently from the condition that the system gives rise no averaged forward-scattering. This condition provides us E-k relation of the system. An expression of the local density of states is derived.