Reaction kinetics of the CN radical with methyl bromide

Abstract

The kinetics of the CN+CH 3 Br reaction were studied using transient infrared laser absorption spectroscopy to detect CN reactants and HCN products. This reaction has a rate constant of k = (2.20±0.6)10-12 exp (453±98/T) cm 3 molecule-1 s-1 over the range 298-523 K. Hydrogen abstraction to produce HCN + CH 2 Br is only a minor reaction product, with a branching fraction of 0.12±0.02. Other product channels, including BrCN + CH 3 , CH 2 CN + HBr, CH 3 CN + Br are likely. An upper limit of 0.01 was established for the HBr yield. These results are in qualitative agreement with recent ab initio calculations.