Lattice Dynamics of Sodium Azide. A Group-Theoretical Analysis

Abstract

The symmetry properties of normal modes of the lattice vibrations of sodium azide are investigated. The formalism suggested by Maradudin and Vosko, which is relevant for the present study, is summarized. Symmetry vectors at several points of the Brillouin zone are determined. Interrelationships between the elements of the dynamical matrix have been evaluated. The compatibility relations among the dispersion curves for various wave vectors are also derived.