The local vibrational modes of group-II acceptor-H complexes were studied by means of infra-red absorption spectroscopy. In addition to previously observed Zn-H complexes, modes were reported which corresponded to Be-H and Cd-H complexes. In the case of Be-doped material, modes at 2292.2 and 1669.8/cm were attributed to the P-H and P-D bond-stretching modes of complexes that were adjacent to the Be acceptors. In the case of Cd-doped material, modes at 2434.0 and 1768.3/cm were attributed to similar complexes that were adjacent to the Cd acceptors. Temperature-dependent shifts in the H local vibrational modes in Be-doped and Zn-doped material were shown to be proportional to the lattice thermal energy. This was suggested to be a consequence of anharmonic coupling between the local vibrational modes and the lattice phonons.

M.D.McCluskey, E.E.Haller, J.Walker, N.M.Johnson: Physical Review B, 1995, 52[16], 11859-64