Study of the I·CO2 van der Waals complex by threshold photodetachment spectroscopy of I–CO2

Abstract

Photodetachment of the I^–CO₂ anion accesses the three lowest-lying electronic states of the I·CO₂ van der Waals complex. High-resolution threshold photodetachment (ZEKE) spectroscopy reveals progressions in the low-frequency C–I van der Waals stretch in each electronic state, providing a detailed spectroscopic probe of the interaction between a halogen atom and a closed-shell molecule. From our data, we construct one-dimensional potential-energy functions for each neutral state as well as for the anion, and these are compared to rare-gas–halogen and rare-gas–halide potentials.