Molecular structures of dimethylgermyl dibromide and methylgermyl tribromide determined by vapour-phase electron diffraction

Abstract

The molecular structures of GeBr₂Me₂ and GeBrMe₃ have been determined by vapour-phase electron diffraction. The geometrical parameters based on the r_g interatomic distances are as follows: for GeBr₂Me₂; r(C–H)= 1.12 (assumed), r(Ge–C)= 1.91 ± 0.01, and r(Ge–Br)= 2.303 ± 0.002 Å, angle BrGeBr = 104 ± 1, CGeBr = 107 ± 3, CGeC = 124 ± 7, and GeCH = 105 ± 6°; for GeBr₃Me; r(C–H)= 1.12 (assumed), r(Ge–C)= 1.89 ± 0.03, and r(Ge–Br)= 2.276 ± 0.002 Å, angle BrGeBr = 107.1 ± 0.4, CGeBr = 111.6 ± 0.3, and GeCH = 109.5°. The quoted uncertainties have been estimated to include both systematic and random errors. In neither case could the analysis deterrmine the rotational positions of the methyl groups because the scattering components due to distances involving hydrogen are too weak.