Determination by electron diffraction of the molecular structure of tris(trimethylsilyl)methylphosphine in the gas phase

The molecular structure of (Me3Si)3CPH2 in the gas phase has been determined by electron diffraction. Important bond lengths (ra) are Si–C 194.1(5), Si–Me 188.3(2), and P–C 180.8(9) pm. Steric strain within the tris(trimethylsilyl)methyl group is relieved by (a) compression of the methyl groups within each trimethylsilyl group, so that the Me–Si–Me angles are only 104.3(4)°, (b) tilting of the trimethylsilyl groups by 7.3(15)° away from each other, and (c) twisting of the trimethylsilyl groups by 21.2(4)° away from the fully staggered conformation.