Anion Photoelectron Spectroscopy and High Level Ab Initio Calculations of the Halide-Nitric Oxide Dimer Complexes

Anion photoelectron spectra are presented for gas phase complexes formed between halide anions and nitric oxide, X-center dot center dot center dot NO where X- = Cl-, Br-, and I-. Electron binding energies are experimentally determined to be 3.82, 3.51, and 3.17 eV. Results from CCSD(T)/aug-cc-pVTZ calculations are presented for the anion species, whereby a single minimum of Cs symmetry is predicted. Binding energies ( D0) of 15.3, 13.3, and 11.7 kJ mol(-1) are predicted from complete basis set limit extrapolation, and are found to be in line with previous experimental studies.