The Canonical Transformation Theory and its application to the Reaction Path Hamiltonian

The reaction path Hamiltonian is formulated using the canonical transformation theory of classical mechanics. A method for checking the accuracy of the reaction path approach is presented, being based on the definition of a functional depending on the system Lagrangian. It is shown that the difference between the classical exact and the reaction path Hamiltonian dynamics can be expressed in terms of the potential energy sampled during the corresponding trajectories.