Potential energy surface and rate constant of the inversion substitution reactions CH3X+O2 → CH3O2•+X• (X=SH, NO2)

The temperature dependence of the rate constant of the inversion substitution reactions CH₃X+O₂ → CH₃O₂^•+X^• (X=SH, NO₂), can be expressed as k=6.8×10^–12(T/1000)^1.49exp(–62816 cal mol^–1/RT) cm³ s^–1 (X=SH) and k=6.8×10^–12(T/1000)^1.26××exp(–61319 cal mol^–1/RT) cm³ s^–1 (X=NO₂), as found with the use of high-level quantum chemical methods and the transition state theory.