High-resolution electronic spectroscopy of the Ne-OH and Ne·OD A ← X bands

The high-resolution laser-induced fluorescence spectra of the Ne·OH A (0, 1¹, 1) ← X (0, 0⁰, 0) and Ne·OD A (0, 0⁰, 0) ← X (0, 0⁰, 0), A (0, 0⁰, 1) ← X (0, 0⁰, 0), A (0, 1¹, 1) ← X (0, 0, 0), A (0, 1¹, 1) ← X (0, 0⁰, 0) transitions were obtained. Analyses of these spectra determine precise bond lengths and reveal interesting spin-rotation and parity structure. In the A (0, 1^{K=0, 1}, 1) levels of Ne·OH and Ne·OD, the spin-rotation structure is described with the parameter y, whose magnitude is larger than in the other observed levels of Ne·OH, Ne·OD, and Ar·OH, and Ar·OD. For the K = 1 level an additional term K is introduced and is found to be an order of magnitude larger than y. A model based on perturbation theory is proposed and successfully explains the peculiar spin-rotation structure in the A (0, 1^K, 1) levels. In addition, a parity-splitting (P-type doubling) for the X (0, 0⁰, 0) level of Ne·OD was determined to be a factor of 10 larger than that in Ar·OD. The parity splitting (K-type doubling) for the A (0, 1¹, 1) level of Ne·OH is also observed and measured.