Photoelectron imaging of several 5d and 6p Rydberg states Xe2 and improving the Xe2+ I(1/2g) potential

Abstract

Velocity map photoelectron imaging was used to study the photoionization of Xe(2) in several low-lying 5d and 6p Rydberg states. The Rydberg states were prepared by two-photon excitation and ionized by either one additional photon from the pump laser (2+1 ionization), or by one photon of a second color (2+1(') ionization). The 2+1 images and associated photoelectron spectra were consistent with previous results, although some adjustment of previously proposed equilibrium bond lengths was necessary to fit the spectra with Franck-Condon factor calculations. The 2+1(') images provided higher resolution photoelectron spectra and, in conjunction with the Xe(2)(+) potentials reported by Zehnder and co-workers [J. Chem. Phys. 128, 234306 (2008)] and the 6p and 5d Xe(2)∗ potentials calculated by Jonin and Spiegelmann [J. Chem. Phys. 117, 3059 (2002)], provided a means for improving the Xe(2)∗ potentials. New experimental data are also presented for photoionization populating the Xe(2)(+) I(1∕2g) state, and are used to provide a better description of its potential curve.