Ring, Chain, and Cluster Compounds in the Cl−Ga−N−H System

The formation of gas-phase oligomer compounds in the Cl−Ga−N−H system is considered using hybrid Hartree−Fock/density functional theory and a polarized double-ζ quality basis set. Geometric parameters, vibrational frequencies, and thermodynamic characteristics for the Cl₃GaNH₃ adduct, its dissociation products GaCl_n, NH_n, (n = 1−3), the amidochlorogallanes [Cl₂GaNH₂]_n (n = 1−3), their donor−acceptor complexes with GaCl₃ and NH₃, and the imidochlorogallanes [ClGaNH]_n (n = 1−4,6) have been obtained. Generation of amidochlorogallanes is expected to be viable during laser assisted chemical vapor deposition (CVD) at low temperatures. High-temperature association processes in the gas phase during the CVD of GaN from the Cl₃GaNH₃ adduct are predicted to be less important, in contrast to previous findings for the aluminum analogue. This difference may be explained in terms of a much lower Ga−N bond energy compared to Al−N in the ring and cluster compounds.