Knowledge Bank

A single determinantal SCF wave function has been obtained for the $a3\Pi$ state of CO. The calculations were carried out at the experimental $Re$ of this state. The electronic configuration of this is $1\sigma 22\sigma 23\sigma 24\sigma 25\sigma 1\pi 42\pi$. The molecular orbitals are expanded in terms of 24 Slatertype functions, 16 of $\sigma$ symmetry and 8 of $\pi$ symmetry. The expansion coefficients are determined variationally, using Roothann's open shell SCF $formulism.1$ The calculations started out with a basis set carefully optimized to represent the ground state of $CO.2$ Modifications of the basis set were then made, by substituting with different types of basis functions, to make it a better representation of the excited state charge distribution. Exponents of this modified set were re-optimized for the excited state. A number of one electron molecular properties are evaluated with the wave function. They are to be compared with the recent molecular beam experiment $data3$ on this state.