Disulfide Bond in Diethyl Disulfide: A Rotational Spectroscopic Study.

Diethyl disulfide was investigated by pulsed jet Fourier transform microwave spectroscopy. The spectroscopic study was complemented by ab initio calculations. The first two most stable conformers predicted at the MP2/6-311++G(d,p) level of theory were observed in the supersonic expansion. Two 13C and one 34S isotopologues for the most stable conformer ( GGG) and two 34S isotopes for the second most stable form ( GGG') were also assigned in natural abundance, respectively, allowing a thorough investigation of the molecular structure and conformation. The relative population ratio of the two conformers in the supersonic expansion was estimated to be about 4:1.