Journal of Chemical Physics, Vol.109, No.10, 3944-3953, 1998
Mass-resolved two-photon and photoelectron spectra of Xe-2 in the Xe(4f) region above the first molecular ionization limit
Two-photon resonance enhanced multiphoton ionization (REMPI), time-of-flight (TOF) mass spectrometry, and photoelectron spectroscopy have been used to investigate the gerade Xe-2 Rydberg states located just above the first molecular ionization limit. Effective vibrational analyses are presented for live dimer states that dissociate to Xe+Xe*(4f). The electronic symmetries of the band systems in this region were deduced from separate REMPI spectra recorded with linearly and circularly polarized laser light while excited state bond lengths were estimated from Franck-Condon intensity simulations. Two photoelectron signals were measured for each molecular resonance examined in this work. The strongest one, having a near zero kinetic energy, is attributed to dimer electrons released through autoionization. The weaker photoelectron signals corresponding to faster electrons originate from excited state Xe atoms formed by predissociation.
Keywords:ENHANCED MULTIPHOTON IONIZATION;ION-CORE ASSIGNMENTS;2-PHOTON SPECTROSCOPY;VIBRATIONAL STRUCTURE;POTENTIAL CURVES;RYDBERG STATES;GROUND-STATE;XE2;DIMERS;XE-ASTERISK(5D)