An integral-equation approach to the electronic structure of liquid silicon

Abstract

We have extended an integral-equation approach (proposed by Winn and Logan, and, in parallel, by Stratt and co-workers) for the determination of the electronic density of states of disordered materials within the `tight-binding' framework to the case of an model. This formalism leads to a set of coupled complex-valued integral equations which turn out to be formally equivalent to the Ornstein - Zernike equations of an ion - dipole mixture. As a closure relation, which is required for the solution, we have used a linear relation. In order to check the reliability of this approach we have complemented the integral-equation data with results from a `tight-binding' molecular-dynamics simulation. As an example we chose liquid silicon, using the `tight-binding' parametrization proposed by Goodwin et al. The agreement of the two sets of data is very satisfactory.