Lattice dynamics of mixed crystals: HCl–DCl

Abstract
The method of ``negative eigenvaluetheorem'' has been applied for the determination of the vibrational density of states of mixed crystals of HCl and DCl. The corresponding atomic motions have been derived, thus making it possible to understand the dynamics of these systems. The fitting with the infrared spectrum has been obtained by weighting the density of states with a transition moment based on a rigid ion assumption.