title: Overtone spectroscopy of H2O clusters in the V(OH) = 2 manifold: infrared-ultraviolet vibrationally mediated dissociation studies.
abstract: Spectroscopy and predissociation dynamics of (H2O)2 and Ar-H2O are investigated with vibrationally mediated dissociation (VMD) techniques, wherein upsilon(OH) = 2 overtones of the complexes are selectively prepared with direct infrared pumping, followed by 193 nm photolysis of the excited H2O molecules. As a function of relative laser timing, the photolysis breaks H2O into OH and H fragments either (i) directly inside the complex or (ii) after the complex undergoes vibrational predissociation, with the nascent quantum state distribution of the OH photofragment probed via laser-induced fluorescence. This capability provides the first rotationally resolved spectroscopic analysis of (H2O)2 in the first overtone region and vibrational predissociation dynamics of water dimer and Ar-water clusters. The sensitivity of the VMD approach permits several upsilon(OH) = 2 overtone bands to be observed, the spectroscopic assignment of which is discussed in the context of recent anharmonic theoretical calculations.
authors.affiliation: JILA, University of Colorado, Boulder, Colorado 80309, USA.
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Nizkorodov
authors.forename: Michael
authors.initials: M
authors.lastname: Ziemkiewicz
authors.forename: David J
authors.initials: DJ
authors.lastname: Nesbitt
authors.forename: Alan E W
authors.initials: AE
authors.lastname: Knight