Photoelectron spectroscopy of ClH2- and ClD2-:: A probe of the Cl+H2 van der Waals well and spin-orbit excited states

Photoelectron (PE) spectra of ClH2- and ClD2- were measured at 299 nm (4.154 eV). Photodetachment of these anions accesses the prereactive van der Waals well on the ground state Cl+H-2 potential energy surface, as well as the low-lying spin-orbit excited states resulting from the interaction of Cl and Cl* with H-2. The PE spectra are dominated by two relatively narrow peaks corresponding to transitions to the neutral Cl . H-2 and Cl* . H-2 complexes. The energetics and widths of these features are interpreted in terms of the properties of the anion and neutral potential energy surfaces. (C) 2002 American Institute of Physics.