A discharge–flow study of the kinetics of the reactions of IO with CH3O2 and CF3O2

Abstract

We have determined the rate constants for the reactions IO + CH₃O₂ → Products (1) and IO + CF₃O₂ → Products (2) using a discharge–flow tube equipped with off-axis cavity-enhanced absorption spectroscopy (CEAS) for the detection of IO. NO₂, produced from the titration of RO₂ with NO, was also detected using the CEAS system. The rate constants obtained were k₁ = (6.0 ± 1.3) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ and k₂ = (3.7 ± 0.9) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at T = 295 ± 2 K and P = 2.5 ± 0.3 Torr; this is the first determination of these rate constants. The possible products and the atmospheric implications of reaction (1) are discussed.