Binding energy and related properties of silicon

Pseudopotential theory has in the past been applied with considerable success to the calculation of the binding energy and related properties such as equilibrium atomic volume for non‐transition metals, particularly Na, Mg, Al. Its application to Si is considered here. Results for the f.c.c. structure, as well as the observed semiconducting phase with diamond structure and the metallic (white Sn) phase found under pressure, are presented and discussed. In the case of the semiconducting phase, the theory must be modified to include “covalent” contributions to the binding energy, and this is done in a crude way using Van Vechten's result for the total energy of occupied states in the isotropic semiconductor (“Penn”) model.