Electron affinity of the methyl radical: Structures of CH 3 and CH 3 -

Ab initio self-consistent field and configuration interaction calculations are presented for the methyl radical and anion. The methyl radical is shown to be planar (D(3h)), while the anion is pyramidal (C(3v)). The methyl anion is unstable with respect to the limit of CH(3) plus an electron by 2-8 kcal/mole. Potential curves for the out-of-plane bending motions of both molecules are presented.