Kwiseon Kim Walter R. L. Lambrecht Benjamin Segall 1996 Elastic constants and related properties of tetrahedrally bonded BN AlN GaN and InN Physical Review B vol. 53 no. 24 pp. 16310-16326
In the experimental side
the elastic constants, are important since they are related to hardness and therefore of interest in applications where mechanical strength and durability are important. The elastic constants of gallium nitride ͑GaN͒ have only been estimated from the mean square displacement of the atoms measured  by x-ray diffraction
we present the results of a Brillouin scattering in vestigation of the elastic constants of hexagonal GaN. Our
experiments were performed on a hexagonal, needle-like single crystal roughly 500 ␮ m along the c axis and 200 ␮ m in diameter; it also had well-formed facets at the ends of the needle thereby enabling a variety of scattering geometries to be used. The crystals were grown at high pressure and high temperature ͑1500–1700 K͒
A. Polian, M. Grimsditch, I. Grzegory, 1996, Elastic constants of gallium nitride, Journal of Applied Physics, vol. 79, no. 6, pp. 3343-3344