PNNL

Abstract

The electronic structure of ClOx (x = 2-4) radicals were experimentally investigated using anion photoelectron spectroscopy of the respective anions at several photon energies. The electron affinities of ClO3 and ClO4 were obtained for the first time and were found to be very high, 4.25?0.10 and 5.25?0.10 eV, respectively. Three low-lying excited states were observed for ClO2 with excitation energies of 2.10 eV (2B2), ~2.60 eV (2A1 and 2A2). The 2A1 and 2A2 states were found to be nearly degenerate. Two low-lying states were observed for ClO3 at ~1.20 eV (2A2) and ~2.65 eV (2E), whereas no excited state was observed for ClO4 even at our highest photon energy of 157 nm (7.866 eV). The photoelectron spectra were assigned and compared with available theoretical calculations. The excellent agreement between the experimental and theoretical results confirmed the previous calculations.