Reaction of the i-C4H5 (CH2CCHCH 2) radical with O2

Abstract

The resonantly stabilized radical i-C4H5 (CH 2CCHCH2) is an important intermediate in the combustion of unsaturated hydrocarbons and is thought to be involved in the formation of polycyclic aromatic hydrocarbons through its reaction with acetylene (C 2H2) to form benzene + H. This study uses quantum chemistry and statistical reaction rate theory to investigate the mechanism and kinetics of the i-C4H5 + O2 reaction as a function of temperature and pressure, and unlike most resonantly stabilized radicals we show that i-C4H5 is consumed relatively rapidly by its reaction with molecular oxygen. O2 addition occurs at the vinylic and allenic radical sites in i-C4H5, with respective barriers of 0.9..