Perturbation analysis of the <i>B</i> 1Π state of 23Na85Rb molecule

Abstract

A number of the rovibrational levels of the B 1Π state are found to be strongly perturbed. The energy shifts of the e and f levels of the B 1Π state are studied, and the perturbations between the B 1Π and (2) 3Σ+ states and between the B 1Π and (1) 3Π1 states are identified. Forty-seven centers of perturbation are observed, and the molecular constants of the (2) 3Σ+ and (1) 3Π1 states are estimated. The hyperfine splitting of the (2) 3Σ+ state is observed. Each rovibrational level splits primarily into four lines, and each of the four lines splits into six lines. The splitting is identified as originating from the magnetic dipole interaction primarily with the nuclear spin of 23Na (I=3/2) and secondarily with the nuclear spin of 85Rb (I=5/2).