The reaction path of the rcaction HCN + OH - CN + H2O was traced with Fukui’s theory of intrinsic reaction coordinate by using ab ini tio MO method (at UMP4/6-31G** level) with gradient technique. On this basis, the dynamics properties along the reaction path was investigated by reaction path Hamiltonian theory. The rate constants of this reaction at different temperatures were calculated by conventional and variational transition state thcory with tunneling correction.The theoretically calculatcd rate constants are in good agreement with experimental results, this shows that the title reaction is an one step,direct reaction.
