The Microwave Spectrum of Dimethyl Sulfone

The microwave spectra of normal and 13C-isotopic species of dimethyl sulfone have been investigated, and the rotational constants of both species have been determined. The following r0-structural parameters have been determined: r(C–S)=1.777±0.006Å, r(S–O)=1.431±0.004Å, ∠CSC=103°17′±10′, and ∠OSO=121°1′±15′, assuming that r(C–H)=1.091Å and ∠HCH=109°34′. The variations in the structural parameters among the related alkyl sulfides, alkyl sulfoxides, and alkyl sulfones have been discussed. The dipole moment has been determined to be μ=4.432±0.041 D along the b axis. This value is consistent with the results of a bond-moment calculation based on the dipole moment of dimethyl sulfoxide.