RESONANCE ENHANCED (2 + 1) MULTIPHOTON IONIZATION SPECTRUM OF BR-2 - THE LOWER RYDBERG STATES

The resonance enhanced (2+1) multiphoton ionization spectrum of Br2 has been recorded in the region 61000-85000 cm-1 and gerade Rydberg states up to n=11 have been identified. Two series are seen, based on the Ω= 3 2 g and 1 2 g core states. All of the higher states are members of the ns series but four components of the [Ω] 4d multiplet close in energy to [Ω] 6s have been identified for the first time. The quantum defects are very similar to those of the Br atom and to those of the lower members of the d series in CH3Br. The s series is at least an order of magnitude more intense than the d series, but intensities within each [Ωc]ns←-X and [Ωc]4d←X multiplet present some unexpected features. © 1990.