14740-53-5Relevant academic research and scientific papers
Formation of digallium sites in the reaction of trimethylgallium with silica
Taha, Ziyad A.,Deguns, Eric W.,Chattopadhyay, Swarup,Scott, Susannah L.
, p. 1891 - 1899 (2006)
The room-temperature, gas-solid reaction of volatile GaMe3 with a nonporous silica was studied by elemental and gas-phase analysis, in situ IR and 1H, 13C, and 29Si solid-state NMR, and extended X-ray absorption fine structure (EXAFS) spectroscopy. Most of the grafting (～85%) occurred on Q3 sites, O3SiOH, but a small amount (～15%) of siloxane (O3SiO-SiO3) bond cleavage was also observed. The major, if not the only, gallium product has the empirical formula ≡SiOGaMe2, but it is not an isolated site. The Ga K-edge EXAFS of GaMe3-modified silica, recorded at 10 K, reveals that each Ga has a Ga neighbor at 2.97-2.99 A. The sites are best described as [GaMe 2(μ-OSi≡)]2. To strengthen this assignment, a molecular analogue, [GaMe2(μ-OSiPh3)]2, was characterized by both single-crystal X-ray diffraction and EXAFS. The Ga 2O2 rings in the molecular complex and the silica-supported gallium dimer have very similar dimensions. The gallium dimer is formed on the silica surface regardless of the extent of partial dehydroxylation (varied by pretreatment in vacuo at 100 and 500°C). This result is interpreted in terms of a vicinal disposition for the majority of Q3 grafting sites.
Silylated gallium and indium chalcogenide ring systems as potential precursors to ME (E=O, S) materials
Medina-Ramirez, Iliana E.,Floyd, Cynthia,Mague, Joel T.,Fink, Mark J.
, p. 1225 - 1238 (2013/09/02)
The reaction of R3M (M=Ga, In) with HESiR′3 (E=O, S; R′3=Ph3, iPr3, Et3, tBuMe2) leads to the formation of (Me 2GaOSiPh3)2 (1); (Me2GaOSi tBuMe2)2 (2); (Me2GaOSiEt 3)2 (3); (Me2InOSiPh3)2 (4); (Me2InOSitBuMe2)2 (5); (Me 2InOSiEt3)2 (6); (Me2GaSSiPh 3)2 (7); (Et2GaSSiPh3)2 (8); (Me2GaSSiiPr3)2 (9); (Et 2GaSSiiPr3)2 (10); (Me 2InSSiPh3)3 (11); (Me2InSSi iPr3)n (12), in high yields at room temperature. The compounds have been characterized by multinuclear NMR and in most cases by X-ray crystallography. The molecular structures of (1), (4), (7) and (8) have been determined. Compounds (3), (6) and (10) are liquids at room temperature. In the solid state, (1), (4), (7) and (9) are dimers with central core of the dimer being composed of a M2E2 four-membered ring. VT-NMR studies of (7) show facile redistribution between four- and six-membered rings in solution. The thermal decomposition of (1)-(12) was examined by TGA and range from 200 to 350 C. Bulk pyrolysis of (1) and (2) led to the formation of Ga2O3; (4) and (5) In metal; (7)-(10) GaS and (11)-(12) InS powders, respectively. [Figure not available: see fulltext.]
