Complex Formation in Reactive and Inelastic Scattering: Statistical Adiabatic Channel Model of Unimolecular Processes III

Abstract The statistical adiabatic channel model developed previously 25 for unimolecular dissociation reactions is extended to describe bimolecular collisions proceeding via a strongly bound intermediate complex. As examples three cases are considered, in which the intermediate complex corresponds to a known stable molecule: O + O 2 → O 3 *, O + NO → NO 2 * and Cl + NO → ClNO*. Using known molecular properties and the experimental high pressure recombination rate constants, the specific dissociation rate constants k(E,J) , state to state inelastic scattering cross sections σ( v,j → v',j ') and center of mass translational energy distributions are calculated with the same simple potential model. Rate constants k vv , for vibrational relaxation are computed and found to be in good agreement with experimental results available for the O + O 2 vibrational relaxation. The dependence of cross sections and final state distributions as a function of initial state is illustrated in some detail. Even within the statistical model, there is found to be a marked memory of initial conditions. The range of validity of statistical models is discussed.