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Title: Observation of the fastest chemical processes in the radiolysis of water
Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H 2 O + , remains elusive. We used tunable femtosecond soft x-ray pulses from an x-ray free electron laser to reveal the dynamics of the valence hole created by strong-field ionization and to track the primary proton transfer reaction giving rise to the formation of OH. The isolated resonance associated with the valence hole (H 2 O + /OH) enabled straightforward detection. Molecular dynamics simulations revealed that the x-ray spectra are sensitive to structural dynamics at the ionization site. We found signatures of hydrated-electron dynamics in the x-ray spectrum.
Authors:
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Award ID(s):
1856342
Publication Date:
NSF-PAR ID:
10220384
Journal Name:
Science
Volume:
367
Issue:
6474
Page Range or eLocation-ID:
179 to 182
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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