CS2+(B2Σu+, A2Πu → X2Πg) Fluorescence from Photoionization Excitation of CS2 Vapor

Abstract

CS2+(B2Σu+, A2Πu → X2Πg) fluorescence bands produced by irradiation of CS2 vapor with emission lines from λλ462–977 Å were analyzed and their production cross sections measured. The assignments for the emission bands of the bending transitions, B2Σu+(0ν0) → X2Πg(0ν0), have been suggested. Using the tentatively assigned positions of the band heads for the A2Πu(ν00) → X2Πg(000) transitions the ionization potentials for the A2Πu(ν00) vibrational levels were obtained and found to be in good agreement with the photoelectron data. The splitting constant of the spin–orbit interaction for the A2Πu state was thereby determined to be 169 ± 20 cm−1. The CS2+(A2Πu, B2Σu+ → X2Πg) fluorescence has exceptionally high production cross sections at the absorption bands associated with the n = 3 members of the Rydberg series III and V.