VAPOR-PHASE LASER PHOTOCHEMISTRY AND DETERMINATION BY ELECTRON-DIFFRACTION OF THE MOLECULAR-STRUCTURE OF [((T)BU)GAS](4) - EVIDENCE FOR THE RETENTION OF THE GA4S4 CUBANE CORE DURING THE MOCVD GROWTH OF CUBIC GAS

The vapor phase structure and decomposition of [((t)Bu)GaS](4) have been investigated by gas phase electron diffraction and UV-laser photolysis/time-of-flight mass spectrometry, respectively. The vapor phase structure of [((t)Bu)GaS](4), as determined by electron diffraction, consists of a distorted cubane Ga4S4 core. Salient structural parameters (r(a)) include Ga-S = 2.365(2) Angstrom and Ga-C = 1.976(4) Angstrom. The electron diffraction structure is compared to that determined in the solid state by X-ray diffraction. The gas phase ultraviolet excimer laser-induced photolysis of [((t)Bu)GaS](4) has been studied using a photolysis wavelength of 248 nm. The photofragments were detected by laser ionization time-of-flight mass spectroscopy. The formation of photofragments ((t)Bu)(x)Ga4S4 (x = 0-3) is interpreted to indicate the stability of the Ga4S4 core. Solid state ablation studies additionally indicate the coupling of two cubane cores. These results are discussed with respect to the metalorganic chemical vapor deposition of the cubic phase of GaS, using [((t)Bu)GaS](4) as a single-source precursor.