Rate constants from the reaction path Hamiltonian. I. Reactive flux simulations for dynamically correct rates

A method to construct a transverse eigensystem to analyze the rate constants from the reaction path Hamiltonian in systems with many degenerate transverse frequencies was discussed. Reactive flux calculations were facilitated by the attainment of smoothly varying coupling constants by the diabatically constructed reaction path. The reaction flux formalism could be applied to an ab initio reaction path hamiltonian for a system with 54 degrees of freedom. The results show that the variational transition state theory only accounts for half of the rate constant reduction due to recrossing trajectories.