Calculation of electronic transition matrix elements based on local atomic environment

Abstract

In a wide variety of solids the electronic structure is well described in terms of local atomic environment by the recursion method. A theory of perturbations, directed towards the calculation of transition matrix elements, is developed in terms of the local environment using the recursion method as the unperturbed solution. As well as embodying this physical concept, the theory permits calculations on systems with many more degrees of freedom than other methods.