ABINITIO MO STUDIES ON THE POTENTIAL-ENERGY SURFACE OF THE METHYL-CHLORIDE RADICAL-ANION

The potential energy surface of the methyl chloride radical anion has been studied by ab initio molecular orbital theory. The following calculated results are obtained, different from the reported C-Cl dissociation potential curves: (1) A shallow least energy point (stationary point) is found within C3-nu symmetry in cases where dynamical correlation effects are taken into consideration. (2) The well-known C3-nu dissociation path is not the minimum energy one, and a planar C2-nu minimum geometry is found on the potential energy surface of methyl chloride radical anion. On the C-Cl dissociation minimum energy path, the initial C3-nu structure is changed to the planar C2-nu one by a CH3 rocking deformation. The calculated results also provide a possibility that the experimentally observed methyl radical-chloride ion adduct has the planar C2-nu structure instead of the C3-nu one.