Ab initio MO study on C 4O: structures and electron affinities

Abstract

The geometrical structures of four conformers of the C 4O molecule were surveyed with second- and third-order Møller-Plesset perturbation theory and complete active space SCF methods using the Huzinaga-Dunning double zeta plus polarization basis set. The relative stability of the conformers and the electron affinity of C 4O were calculated by the configuration interaction method (including single and double excitations) with the Davidson correction. The general contraction scheme of the [5s4p2d1f] atomic natural orbital basis set, based on the (14s9p4d3f) primative Gaussian functions, was applied. The linear structure is most stable in both neutral and anionic C 4O. The electron affinity of C 4O was calculated to be 2.77 eV, 0.72 eV larger than the experimental value.