Analysis of Internal Rotation and Determination of the Heavy Atom Structure of anti-2,3-Dimethylthiirane by Fourier Transform Microwave Spectroscopy

We used the advanced technique of Fourier transform microwave spectroscopy to measure and assign the ground state rotational spectrum of anti-2,3-dimethylthiirane, and to analyse the internal rotation of the two methyl groups. The potential parameters obtained are V = 13.1678(21) and V = -1.6678(25) kJ/mol. The measurement and assignment of the C and S isotopomers in the ground state allowed to determine the molecular structure of the heavy atom frame using the Τ and Τ methods.