A theoretical study on the strength of two-center three-electron bond in (CH 3) 2S–OH and H 2S–OH adducts

Abstract

Ab initio and DFT investigations on H 2S–OH and (CH 3) 2S–OH adducts have shown that electron correlation is essential for an accurate description of the two-center three-electron S–O bonds in the adducts. Calculations at the BH&HLYP, B3LYP, MP2, and CCSD(T) levels indicate that the S–O bond in the (CH 3) 2S–OH adduct is considerably stronger and shorter than that in the H 2S–OH adduct. Our best estimate for the dissociation enthalpy at 298 K for the S–O bond in the (CH 3) 2S–OH adduct is 9.0 kcal/mol, which is in satisfactory agreement with experimentally derived values.