Zero electron kinetic energy spectroscopy of the KrBr-, XeBr-, and KrCl- anions

Three rare-gas halide (RgX-) anions, KrBr-, XeBr-, and KrCl-, and the corresponding neutral, open-shell van der Waals complexes are studied with anion zero electron kinetic energy spectroscopy. The spectra for each system reveal well-resolved progressions in the low frequency vibrations of the anion and one or more of the three neutral electronic states accessed by photodetachment, providing a detailed spectroscopic probe of the Rg - X- and Rg - X interaction potentials. In the case of KrBr-, transitions to all three of the 'covalent' neutral electronic states (the X1/2, I3/2, and II1/2 states) were observed. For XeBr-, transitions to the X1/2 and II1/2 neutral states were observed. For KrCl-, only the X1/2 state could be studied. From our data, we construct model potentials for the anion and each observed neutral state, and these are compared with other experimental and theoretical potentials. copyright 1998 American Institute of Physics