Gas electron diffraction analysis on S-methyl thioacetate, CH3(O)SCH3

The molecular structure of S-methyl thioacetate, CH3C(O)SCH3, was determined by gas electron diffraction (GED) with the assistance of quantum chemical calculations (B3LYP/6-31G* and MP2/6-31G*). Experimental and theoretical methods result in a structure with syn conformation (C=O double bond syn with respect to the S-C(H-3) single bond). The following skeletal geometric parameters were derived from the GED analysis (r(a) values with 3sigma uncertainties): C=O = 1.214(3), C-C = 1.499(5), S-C(sp(2)) = 1.781(6), S-C(sp(3)) = 1.805(6) Angstrom, O=C-C = 123.4(8)degrees, O=C-S 122.8(5)degrees and C-S-C = 99.20degrees.