Laser-induced fluorescence of the NaRb molecule

Abstract

Several series of laser‐induced fluorescence lines of the heteronuclear alkali dimer NaRb have been observed when a mixture of sodium and rubidium is irradiated by the He–Ne, Ar⁺, or Kr⁺ laser line. The spectroscopic constants of the X ¹Σ⁺ ground state have been determined and the potential energy curve has been calculated by the RKR method. RKR potential curves for the excited B ¹Π and D ¹Π have been determined by comparing the observed and calculated intensity distributions as well as the transition energies. The dependence of the transition dipole moment upon the internuclear distance has been estimated. The fluorescence of the D lines of Na and Rb atoms and a less intense fluorescence, which is assigned as a transition to the a ³Σ⁺ state in NaRb, have been observed. From the measured vibrational spacing, which can be followed close to the dissociation limit, the dissociation energy D^e of the a ³Σ⁺ state is determined to be 568±5 cm⁻¹.