Cyclotrigallazane, [H2GaNH2]3, was prepared by condensing liquid ammonia onto solid trimethylamine gallane, GaH3(NMe3), at −78 °C and allowing the mixture to warm to room temperature and was characterized by IR, mass spectroscopy, elemental analysis, single-crystal X-ray, and neutron powder diffraction. Single-crystal X-ray diffraction at T = −167 °C established that the (GaN)3 ring was in the chair conformation. Neutron powder diffraction data collected at 25 °C on the fully deuterated analogue were analyzed with Rietveld refinement to give an average bond distance for Ga−D of 1.56(3) Å and a N−D of 1.04(5) Å. The intermolecular interactions were dominated by four Ga−H···H−N unconventional hydrogen bonds per molecule that form a chain parallel to the crystallographic a axis. The crystallographically equivalent D···D bond lengths are 1.97 Å. Calculations revealed that in the gas phase, twist-boat conformations are preferred over chairs for cyclotrigallazane and the related boron and aluminum compounds by 0.9 to 2.6 kcal/mol at correlated levels of electronic structure theory. For cyclotriborazane and cyclotrigallazane, calculations suggest that each H···H hydrogen bond contributes about 3 kcal/mol to the binding energy (relative to the chair monomer); this value is very slightly higher for cyclotrialumazane.

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Organometallic aluminum azides have been found to be effective precursors for the low temperature chemical vapor deposition of thin films of aluminum nitride. Quantitative analysis of the gas phase products of the reaction are used to develop an understanding of the reaction. Rate studies of the deposition were performed in the temperature range from 400 to 800°C. Below 525°C, an activation barrier of 26.4 kcal/mol was found, while above 525°C, a value of 5.23 kcal/mol was obtained. The effects of the presence of N-C bonds and the type of Al-N interaction within the precursor are evaluated.

Cyclo-trigallazane, [H2GaNH2]3, is known to form bulk powders of the new cubic phase of gallium nitride upon pyrolysis. An explanation for this unusual example where the molecular structure of the precursor controls the crystal structure of the solid state product is presented. In a hot-wall atmospheric pressure chemical vapor deposition (CVD) reactor, arsine was found to react with TMAG to form films of polycrystalline GaAs which were characterized by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The growth rates for smooth films was 1-4 μm/h. In a low pressure CVD reactor, elemental arsenic vapor was also found to react with the TMAG to give GaAs thin films.

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