Quasiclassical study of a termolecular reaction: Application to the HO2 collisional stabilization process

We present a multiprocess reaction dynamics program to study the termination reaction H + O-2 + M -> HO2 + M, one main uncertainty source in hydrogen combustion studies. We simulate the behavior of a mixture of hydrogen atoms and oxygen molecules at different conditions of temperature and pressure, using classical mechanics and accurate Potential Energy Surfaces. In this simulation we treat all the reaction channels, including the stabilization step, in the same dynamical procedure. The contribution of the collisional effects on all the reactions is also accounted for. Following the fate of the excited HO2* radical, we analyze the collisional stabilization and estimate the kinetic parameters of the involved reactions. A Lindemann-Hinshelwood type reaction scheme is shown to be able to describe the kinetics of this reaction as a function of pressure and temperature. This way, we propose a procedure to directly study termolecular reactions.