Lattice dynamics of CdGeP2

The bond parameters for the nearest neighbors have been determined along with the ion charges for CdGeP₂ on the basis of infrared reflection; the Cd-P and Ge-P bond matrices are similar to those for InP and GaP. The ion charges agree with those calculated from the dielectric theory. The lattice-vibration spectrum has been calculated in the long-wave limit for directions of high symmetry. The nonanalytic behavior of the frequency in the long-wave limit has also been examined. The oscillator strengths have been calculated for the optically active frequencies, and the components of the tensor for the static dielectric constant agree well with experiment.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 109–113, June, 1976.We are indebted to Dr. Bettini for making available his results before publication.