Theoretical study of structural and vibrational properties of (AlP)n, (AlAs)n, (GaP)n, (GaAs)n, (InP)n, and (InAs)n, clusters with n=1, 2, 3

The structure, geometry, and vibrational frequencies of several isomers of small group Ill-V (MX)(n) clusters (n = 1, 2, 3; M = Al, Ga, In; X = P, As) have been investigated using density Functional theory. The results reveal the same behavior as in the nitride clusters for monomers and dimers. The At trimers exhibit a D-3h structure like the nitride, but the gallium and indium trimers exhibit a three-dimensional structure of C, symmetry. The existence of strong X-X bonds dominates both the structure and the vibrations of the Ga and in trimers.