Abstract
A method has been derived for the analytic description of potential surfaces in natural reaction coordinates as a preliminary stage in researching the dynamics of SN2-type reactions X−+CH3Y→CH3X+Y−; a potential surface is specified by the potential profile V(s) along the reaction path s, the dependence of the frequencies of the transverse vibrations ωs(s) on s, and the path curvature g(s). V(s) and ωs(s) have been constructed from nonempirical calculations in the 4–31G basis for the energies, geometrical parameters, and vibrational frequencies of the reactants, products, transitional states, and prereaction and postreaction complexes. The parameters of g(s) have been chosen from the condition for the reaction path to pass through all the stationary points on the potential surface. This way of describing a surface leaves adequate freedom for correcting the energy parameters by reference to thermochemical measurements, as well as for examining the effects of the parameters on the reaction dynamics.
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Translated from Teoreticheskaya i Éksperimental'naya Khimiya, No. 3, pp. 271–280, May–June, 1986.
I am indebted to A, I. Beldyrev for providing the program for the quantum-chemical calculations.
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Ryaboi, V.M. Nonempirical calculations on potential surfaces for gas-phase SN2 nucleophilic substitution reactions. Theor Exp Chem 22, 253–260 (1986). https://doi.org/10.1007/BF00521149
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DOI: https://doi.org/10.1007/BF00521149