Kinetics of unimolecular breakdown. VII. Statisticomechanical aspects

The concepts of statistical mechanics are examined from the point of view of application to chemical kinetics. The occurrence of a chemical reaction is considered as an example of an irreversible behavior, and is discussed as due to the combination of system dynamics and experimental conditions. The Lindemann mechanism for thermal unimolecular reactions is discussed on the basis of the relative magnitudes of the various relaxation times. The significance of the random-phase assumption is discussed on the basis of the uncertainty relation between the occupation number and the phase. A master (Pauli) equation is derived and applied to vibrational relaxation. The construction of classical models for unimolecular fragmentation and the significance of computer simulation studies are considered.