Kinetic Modeling of CO Production from the Reaction of CH3with O2in Shock Waves

CO concentration‐time profiles have been measured by using CO laser resonance absorption in shock tube experiments on the reaction of CH3with O2in the temperature range from 1150 to 1560 K. Computer kinetic modeling of our profile data yieldedk2= 1.0 x 1014e−(15,500 ± 1,100)/Tcm3mol sec for the CH3+ O2→ CH3O + O reaction. An RRKM calculation, which took into consideration branching of the CH3+ O2reaction into different product channels, revealed that by assuming a loose transition state (allowing two free internal rotations) leading to the CH3O + O product channel, we could account very satisfactorily for our results as well as those reported previously for the reaction. A three‐parameter leastsquares fit of a smooth curve covering data from three independent studies gave rise to the expression:k2= 2.20 x 1034(T/K)−5.94exp (–21,300 K/T) cm3mol sec for the temperature range 1150‐2300 K.