Electronic ground state and wavefunctions for scandium monoxide

Abstract:

Approximate wavefunctions for ScO have been calculated by the method of Roothaan to establish the ground-state assignment of the molecule. Experimental analysis leads to a ⁴∑ ground state, but this assignment has been questioned. The wavefunctions have been calculated with a limited basis in the matrix Hartree-Fock approximation at three internuclear distances about the minimum in the binding-energy curve. Basis functions of Slater type were selected to include effects of distortion and polarization. Preliminary and final calculations at every stage of computation yielded a ²∑ ⁺ ground state of configuration which is largely σ ²π⁴σ. No other states were found to be near degenerate with this in the region of equilibrium separation reported for the experimental ⁴∑ ground state. It is concluded from this and discussions of possible refinements to the present calculations that ²∑⁺ is the ground state of the molecule. It seems reasonable that the observed band structure can be explained as arising from a ²∑⁺ ground state with a large hyperfine splitting, possibly owing to the fact that at equilibrium separation ScO is approximately Sc²⁺(4s²S)O^2- (¹S). Ground-state parameters calculated here are D<inf>e</inf>≥6.5 eV, r<inf>e</inf> = 1.615 Å, ω<inf>e</inf> = 1373 cm^-1, compared with the experimental values D<inf>e</inf> = 6.9 eV, r<inf>e</inf> = 1.668 Å, ω<inf>e</inf> = 971.55 cm^-1 reported for the apparent ⁴∑ state.

Año de publicación:

1965

Keywords:

Fuente:

scopus