X-RAY CRYSTAL-STRUCTURE OF A MONOMERIC TRIS(ARSINO)GALLANE, [(ME(3)SI)(2)AS]GA-3

The solid-state structure of [(Me(3)Si)(2)As]Ga-3 (1) has been establi shed by single-crystal X-ray analysis. Triclinic crystals of 1 belong to the space group P ($) over bar 1, with a = 10.7529(23), b = 10.7899 (23), c = 17.55(6) Angstrom, alpha = 88.077(23)degrees, beta = 84.537( 23)degrees, gamma = 60.282(16)degrees for Z = 2. Refinement of atomic parameters converged at R=0.058 (R(w) = 0.064) for 2378 observed refle ctions with I > 2.5 sigma(I). The monomeric molecule adopts a trigonal planar configuration with Ga-As = 2.4171(23), 2.4250(22) and 2.4213(2 4) Angstrom, and As-Ga-As (av.) = 120.00(1)degrees. Compound 1 is only the second example of a monomeric tris(arsino)gallane to be structura lly characterized in this manner.