STUDY OF THE ARBR-, ARI-, AND KRI- ANIONS AND THE CORRESPONDING NEUTRAL VAN-DER-WAALS COMPLEXES BY ANION ZERO ELECTRON KINETIC-ENERGY SPECTROSCOPY

Three rare gas halide (RgX(-)) anions, ArBr-, ArI-, and KrI-, der Waal s complexes, ArBr, ArI, and KrI, were studied with anion zero electron kinetic energy (ZEKE) spectroscopy. Photodetachment of each anion acc esses the three lowest-lying electronic states (the X1/2, I3/2, and II 1/2 states) of the neutral complex. The spectra for each system reveal well-resolved progressions in the low frequency vibrations of the ani on and the three neutral electronic states, providing a detailed spect roscopic probe of the Rg.X(-) and Rg.X interaction potentials. The lin e shapes observed in the ZEKE spectra are analyzed in terms of the lin e strengths of the underlying rotational transitions. From our data, w e construct the potential energy curve for each neutral state as well as for the anion, and these interaction potentials are compared to pot entials obtained from scattering and ion mobility experiments.