Binary covalent crystals of group IVa elements: Interatomic interaction and properties

Correlations of potential parameters with the atomic weight are used to determine parameters of the interatomic interaction potential for sphalerite-structured AB binary crystals composed of group IVa elements. It is shown that the parameters for elastic (reversible) deformation differ from those for plastic (irreversible) deformation capable of breaking covalent bonds. A calculational procedure is proposed for evaluating the properties of a sphalerite-structured binary crystal consisting of atoms A and B in which the crystal is represented as a diamond-like crystal composed of identical atoms with a mass equal to the harmonic mean of the masses of atoms A and B. The calculated properties of β-SiC and GeSi agree well with earlier estimates. Predictions of properties are presented for other binary crystals of the group IVa elements whose properties have not been reported in the literature.