Electronic Structure of CH2 and CH3

The self-consistent field molecular orbital method is applied to the calculation of the ground states of the CH2 and CH3 molecules. All electrons are explicitly considered but the three- and four-center electron repulsion integrals were approximated. Results are reported for the dissociation energies, excitation energies, ionization potentials, and the hyperfine splitting constants for the Fermi or ``contact'' term. The values reported for the dissociation energies are in poor agreement with experiment but some qualitative insight into the bonding of these molecules is obtained by an electron population analysis.