Statistical thermodynamic description of homogeneous dispersive kinetics.

A statistical thermodynamic interpretation of homogeneous dispersive kinetics (which assumes the existence of a pseudo-equilibrium between a distribution of reagent states and a single activated state, which together define the rate-determining step), coupled with a previous "quantum kinetic" description for this same type of system (Skrdla, P. J. J. Phys. Chem. A 2006, 110, 11494), is found to provide new insights into the kinetics of these conversions. In particular, the change in the (apparent) activation energy with conversion time is shown to be a function of the entropy change associated with the ensemble of reagent molecules as they traverse the activation energy barrier. Using these two "orthogonal" stochastic interpretations of dispersive kinetics, a fundamental physical description of the rate parameter beta in the author's model is obtained.