Core-penetrating Rydberg series of BaF:: Single-state and two-state fits of new electronic states in the 4.4 ≤ n* ≤ 14.3 region

We report results of optical-optical double resonance studies of the Rydberg states of the BaF molecule in the energy region of E = 33 100-38 200 cm(-1) (4.4 less than or equal to n* less than or equal to 14.3). Barium monofluoride molecules have been produced in a resistively heated high-temperature oven from BaF2 powder mixed with a small amount of boron powder. We have observed more than 50 new electronic states. Forty-nine of them have been rotationally analyzed and assigned to eight Rydberg series (four (2)Sigma (+), one (2)Pi, two (2)Delta, and one (2)Phi). Single-state and two-state fits have been carried out. Multiple local perturbations have been analyzed. Formation of supercomplexes in the Rydberg spectrum of BaF has been discussed. (C) 2001 academic Press.