Theoretical studies on the mechanism of the reaction of HCO^.+HCN→HCHO+CN^.

The geometries of the reactants, the transition state (TS) and the products for the reaction HCO^. +HCN→HCHO+CN^. have been optimized by using ab initio method at UHF/6-31G* * level, and the energies were corrected at the MP2//6-31G* * level. The calculated barrier (149. 602 kJ/mol) for the reaction is in good agreement with the experimental data (143. 001kJ/mol). The Intrinsic Reaction Coordinate (IRC) for the reaction is traced by using Morokuma's magnitude method. The variation of the geometries and the potentials for the reaction system are elucidated along the IRC.