Kinetic study of the reaction of IO with CH₃SCH₃

The reaction IO + CH₃SCH₃ → products (3) was studied at room temperature and near 1 Torr pressure of He, using the discharge flow mass spectrometric technique. The rate constant was found to be k₃ = (1.5 ± 0.5) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹. CH₃S(O)CH₃ was detected as a product suggesting the following channel: IO + CH₃SCH₃ → CH₃S(O)CH₃ + I. The rate constant of the reaction IO + IO → products (1) was also measured: k₁ = (3 ± 0.5) × 10⁻¹¹ at 298 K and 1 Torr pressure. The atmospheric implication of reaction (3) is discussed. The results indicate that this reaction could be a potential important sink of CH₃SCH₃ in marine atmosphere.