High-resolution laser spectroscopy of ZrN: The (0,0) band of the A2Π-X2Σ+ transition

Abstract

The A 2Π-X 2Σ + (0,0) band of ZrN between 5620 and 5890 Åhas been studied using laser polarization, laser-induced fluorescence, and wavelength-resolved fluorescence spectroscopy. All the 12 branches expected from a 2Π- 2Σ + transition have been observed and assigned. Both nondegenerate and degenerate perturbations have been found in the Ω = 3/2 component of the A 2Π state. For 90ZrN, nondegenerate perturbations were found at J = 4.5 and 13.5 in the e level and J = 8.5 and 18.5 in the f level of the Λ-doubling components of the A 2Π 3/2 substate. These perturbations were ascribed to an interaction between the A 2Π state and a nondegenerate Σ state, most likely a 4Σ - state. The degenerate perturbations found at J = 39.5, 44.5, and 56.5 with both Λ-doubling components perturbed to the same extent were consistent with a 2Δ state as the perturbing state. A least squares fit of ground state combination differences yielded accurate molecular constants for the ν = 0 level of the X 2Σ + state. © 2001 Elsevier Science.