Ab initio self-consistent all-electron spin-polarized calculations wer
e performed for the ground state and for several low-lying states of t
he CoO molecule using the local-spin-density approximation. The calcul
ated energies and spectroscopic constants are generally in reasonable
agreement with experimental data. Contrary to previous theoretical rep
orts, the ground state of CoO was found to be 4SIGMA- with the lowest-
lying excited state, 4DELTA, at 0.49 eV above the ground state. An ins
ight into the structure of these states is gained through an analysis
of the electronic populations of the orbitals.