The flash photolysis of azomethane. Minor products from the photolysis of methyl radicals and a rate constant for CH3 + NO

Abstract

AbstractThe flash photolysis of azomethane in a quartz reaction vessel produces mainly ethane (>75%) plus smaller quantities of methane, ethylene, and acetylene. The minor products are interpreted quantitatively in terms of methyl radical photolysis at 216 nm to give CH2 and H. This interpretation is substantiated by the dependence of the minor products on flash intensity. The reduction of the ethane yield on adding NO is employed to obtain a rate constant for CH3 + NO as a function of total pressure, based on a value for methyl radical recombination of 4.2 × 10−11 cm3/molec · sec. An RRKM analysis is used to extrapolate the data to give a limiting high‐pressure rate constant for CH3 + NO of (1.2 ± 0.1) × 10−11 cm3/molec · sec at 298°K.