A Pseudopotential Approach for the Green's Function of Electrons in Amorphous Solids

An approximative expression for the averaged Green's function of an amorphous structure with short‐range order is presented. The main assumptions incorporated are that the atomic potential can be represented by a model potential as used in pseudopotential calculations of electronic properties of crystals, and that the amorphous structure can be described by a product of two‐particle correlation functions. A complex energy function is introduced which describes the main features of the averaged Green's function. It can be calculated by solving a modified pseudopotential equation. Using the complex energy spectrum the density of states is calculated as a “lifetime” broadened crystalline density of states.