Rotational magnetic moment of the Na2 molecule in A 1Σ+u state: Perturbation effects

Values and signs of Landè factors (g) have been measured for four rovibronic levels of the A 1Σ+u state of the Na2 molecule. Because of a very small product gτ∼10−12 s, the level crossing signal of a dispersion shape was employed using circular light polarization and mutually orthogonal excitation, observation of laser induced fluorescence, and external magnetic field directions. The effects of the b 3Πu, B 1Πu, and a 3Σ+u states on the g factors of the Na2(A 1Σ+u), as well as their dependence on vibrational and rotational quantum numbers, have been theoretically analyzed. An analytical connection has been found between the constants of Λ doubling (q) and Landè factors of the interacting singlet states. Simple expressions have been found for estimating the effects of distant electronic states on q and the g factors without summing over bounded and integrating over continuum levels of the perturbing state.