We present a thorough spectroscopic study of the van der Waals molecule NaNe. Our molecular beam apparatus, laser scanning system, and frequency reference technique are described in detail. Methods of rotational analysis are discussed. Descriptions of the observed vibration–rotation bands in the A 2Πr–X 2Σ+ and B 2Σ+–X 2Σ+ manifolds are presented. Perturbations in the observed spectra are discussed. Long range analysis techniques are used to determine the vibrational quantum numbering from observed isotopic shifts and to determine excited and ground state potential parameters. We find DeA=145±05 cm−1 at ReA=5.1(1)a0, DeX=8.1(9) cm−1 at ReX=10.0(1)a0, and DeB?3.0(5) cm−1 at ReB?14.4(3)a0.
We have least-squares fit 244 transitions in the mutually perturbing NaNe A 2Π–X 2Σ+ and B 2Σ+–X 2Σ+ excimer band systems using a Hund’s case ’’c’’ basis. Interatomic potentials were determined by matching computed spectroscopic parameters to 43 fitted parameters. This deperturbation analysis implies that the Na atomic angular momentum qunatum numbers—L and S—are also good molecular quantum numbers. NaNe exhibits an intramolecular transition from Hund’s case c to Hund’s case ’’a’’ angular momentum coupling as the internuclear distance is decreased. The nature of this transition is mediated by the shapes, depths, and positions of both the A 2Π and B 2Σ+ van der Waals potentials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.