CLASSICAL-ANALYSIS OF MODE MODE ENERGY-TRANSFER AND DYNAMICS DURING UNIMOLECULAR REACTION - HYDRAZOIC ACID, HYDROGEN-PEROXIDE, DIIMIDE, AND METHYL NITRITE

A classical trajectory analysis is presented of the dynamics of four unimolecular reactions illustrating impulsive mode-mode energy transfer and specific dynamical pathways leading to reaction. Two of these reactions illustrate bond dissociation, and two illustrate cis-trans isomerization. In each of the four cases, a specific pathway is found to be responsible for activation of the reaction coordinate for times just prior to the reactive event. The classical motion along these pathways is found to be locally regular and stable, even though the trajectories are globally chaotic at the energies studied. Correspondence between these fully dimensional realistic molecular studies and earlier formal work on two-dimensional systems is discussed along with implications for unimolecular reaction rate theory.