title: State-resolved spectroscopy of high vibrational levels of water up to the dissociative continuum.
abstract: We summarize here our experimental studies of the high rovibrational energy levels of water. The use of double-resonance vibrational overtone excitation followed by energy-selective photofragmentation and laser-induced fluorescence detection of OH fragments allowed us to measure previously inaccessible rovibrational energies above the seventh OH-stretch overtone. Extension of the experimental approach to triple-resonance excitation provides access to rovibrational levels via transitions with significant transition dipole moments (mainly OH-stretch overtones) up to the dissociation threshold of the O-H bond. A collisionally assisted excitation scheme enables us to probe vibrations that are not readily accessible via pure laser excitation. Observation of the continuous absorption onset yields a precise value for the O-H bond dissociation threshold, 41 145.94 ± 0.15 cm(-1). Finally, we detect long-lived resonances as sharp peaks in spectra above the dissociation threshold.
authors.affiliation: Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne, Station 6, 1015 Lausanne, Switzerland. pavlo.maksyutenko@psi.ch
authors.forename: Pavlo
authors.initials: P
authors.lastname: Maksyutenko
authors.forename: Maxim
authors.initials: M
authors.lastname: Grechko
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Rizzo
authors.forename: Oleg V
authors.initials: OV
authors.lastname: Boyarkin