The lattice dynamics of gallium antimonide has been investigated experimentally using the method of coherent inelastic scattering of thermal neutrons. The frequencies for phonons propagating in the [001], [111], and [110] symmetry directions in an undoped gallium antimonide crystal at 300 K have been determined with an estimated precision of 2%. The sample had a carrier concentration of 4.85 × ${10}^{17}$ holes/${\mathrm{cm}}^3$ (upper limit) at 300 K. Both second-neighbor and first-neighbor shell models (SM) were fitted to the measured phonon dispersion curves. Some systematic trends among the fitted parameters for the first-neighbor SM for the gallium group-V compounds (GaP, GaAs, and GaSb) are discussed. The fitted second-neighbor SM parameters have been used to generate a phonon frequency distribution, which in turn has been used in the calculation of the temperature dependence of the specific heat at constant volume and the Debye $\Theta$.

• Received 8 July 1974

DOI:https://doi.org/10.1103/PhysRevB.11.1587