A Feynman Path Integral Formulation of Quantum Mechanical Transition State Theory

Abstract

Quantum mechanical transition state theory can be formulated with Feynman path integrals. This formulation retains many of the appealing aspects of classical transition state theory, including the most important feature of any quasiequilibrium theory that the thermal rate constant can be estimated without solving for the actual dynamics. The path integral theory also includes the influence of quantum mechanical tunneling and mode quantization on the rate constant. A theory is described for a Kramers-like dynamical correction factor to the quantum rate constant and an application is given for the problem of proton transfer reactions in polar solvents.