Physics – Chemical Physics
Scientific paper
2007-02-16
Physics
Chemical Physics
25 pages, 5 figs, submitted to J Chem Phys
Scientific paper
10.1063/1.2727468
We use transient absorption spectroscopy to monitor the ionization and dissociation products following two-photon excitation of pure liquid water. The two decay mechanisms occur with similar yield for an excitation energy of 9.3 eV, whereas the major channel at 8.3 eV is dissociation. The geminate recombination kinetics of the H and OH fragments, which can be followed in the transient absorption probed at 267 nm, provide a window on the dissociation dynamics at the lower excitation energy. Modeling the OH geminate recombination indicates that the dissociating H atoms have enough kinetic energy to escape the solvent cage and one or two additional solvent shells. The average initial separation of H and OH fragments is 0.7+-0.2 nm. Our observation suggests that the hydrogen bonding environment does not prevent direct dissociation of an O-H bond in the excited state. We discuss the implications of our measurement for the excited state dynamics of liquid water and explore the role of those dynamics in the ionization mechanism at low excitation energies.
Bradforth Stephen E.
Crowell Robert A.
Elles Christopher G.
Shkrob Ilya A.
No associations
LandOfFree
Title Excited state dynamics of liquid water: Insight from the dissociation reaction following two-photon excitation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Title Excited state dynamics of liquid water: Insight from the dissociation reaction following two-photon excitation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Title Excited state dynamics of liquid water: Insight from the dissociation reaction following two-photon excitation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-348428