Further Considerations on the Symmetry Properties of the Normal Vibrations of a Crystal

Abstract

This paper supplements the preceding paper by Maradudin and Vosko on the same subject. Extensions and additions include discussions of (1) the group of the bond, (2) tabulations of the time-reversal invariance criterion, (3) the labeling of experimental dispersion curves, (4) compatibility relations, (5) accidental degeneracies, (6) the use of computers for extracting symmetry information, and (7) application to magnetic normal modes. The chief results of the preceding paper are summarized. Group theory is used to predict the connectivity of the phonon dispersion relations in CsCl and Mg. A collection of corrections to primary references useful in this field is included.