The phonon dispersion curves of cesium bromide have been observed by inelastic neutron scattering in the symmetry directions $\Delta$, $\Sigma$, and $\Lambda$ and along the symmetry line $T$. The measurements were performed at 80 and 300 K using a three-axis crystal spectrometer. The observations have been fitted to various versions of the shell model, and the frequency distribution and the temperature dependence of the Debye temperature have been calculated from the model which gives the best fit to the experimental frequencies.

• Received 24 June 1971

DOI:https://doi.org/10.1103/PhysRevB.4.4617