| Summary: | The neutral complexes [GaCl<sub>3</sub>(E<sup>n</sup>Bu2)] (E = Se or Te), [(GaCl<sub>3</sub>)<sub>2</sub>{<sup>n</sup>BuE(CH<sub>2</sub>)<sub>n</sub>E<sup>n</sup>Bu}] (E = Se, n = 2; E = Te, n = 3), and [(GaCl<sub>3</sub>)<sub>2</sub>{<sup>t</sup>BuTe(CH<sub>2</sub>)<sub>3</sub>Te<sup>t</sup>Bu}] are conveniently prepared by reaction of GaCl<sub>3</sub> with the neutral E<sup>n</sup>Bu<sub>2</sub> in a 1:1 ratio or with <sup>n</sup>BuE(CH<sub>2</sub>)<sub>n</sub>EnBu or <sup>t</sup>BuTe(CH<sub>2</sub>)<sub>3</sub>Te<sup>t</sup>Bu in a 2:1 ratio and characterized by IR/Raman and multinuclear (<sup>1</sup>H, <sup>71</sup>Ga, <sup>77</sup>Se{<sup>1</sup>H}, and <sup>125</sup>Te{<sup>1</sup>H}) NMR spectroscopy, respectively, all of which indicate distorted tetrahedral coordination at Ga. The tribromide analog, [GaBr<sub>3</sub>(Se<sup>n</sup>Bu<sub>2</sub>)], was prepared and characterized similarly. A crystal structure determination on [(GaCl<sub>3</sub>)<sub>2</sub>{<sup>t</sup>BuTe(CH<sub>2</sub>)<sub>3</sub>Te<sup>t</sup>Bu}] confirms this geometry with each pyramidal GaCl<sub>3</sub> fragment coordinated to one Te donor atom of the bridging ditelluroether, Ga-Te = 2.6356(13) and 2.6378(14) Å. The <sup>n</sup>Bu-substituted ligand complexes serve as convenient and very useful single source precursors for low pressure chemical vapor deposition (LPCVD) of single phase gallium telluride and gallium selenide, Ga<sub>2</sub>E<sub>3</sub>, films onto SiO<sub>2</sub> and TiN substrates. The composition and morphology were confirmed by SEM, EDX, and Raman spectroscopy, while XRD shows the films are crystalline, consistent with cubic Ga<sub>2</sub>Te<sub>3</sub> (F‾43<i>m</i>) and monoclinic Ga<sub>2</sub>Se<sub>3</sub> (Cc), respectively. Hall measurements on films grown on SiO<sub>2</sub> show the Ga<sub>2</sub>Te<sub>3</sub> is a p-type semiconductor with a resistivity of 195 ± 10 Ω cm and a carrier density of 5 × 10<sup>15 </sup>cm<sup>-3</sup>, indicative of a close to stoichiometric compound. The Ga<sub>2</sub>Se<sub>3</sub> is also p-type with a resistivity of (9 ± 1) × 10<sup>3</sup> Ω cm, a carrier density of 2 × 10<sup>13</sup> cm<sup>-3</sup>, and a mobility of 20-80 cm<sup>2</sup>/V·s. Competitive deposition of Ga<sub>2</sub>Te<sub>3</sub> onto a photolithographically patterned SiO<sub>2</sub>/TiN substrate indicates that film growth onto the conducting and more hydrophobic TiN is preferred.
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