These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
Time-Resolved Dynamics in Iodide-Uracil-Water Clusters upon Excitation of the Nucleobase
preprintrevised on 16.09.2019, 16:14 and posted on 17.09.2019, 16:49 by Alice Kunin, Valerie S. McGraw, Katharine G. Lunny, Daniel Neumark
The dynamics of iodide-uracil-water (I−·U·H2O) clusters following π-π* excitation of the nucleobase are probed using time-resolved photoelectron spectroscopy (TRPES). Photoexcitation of this cluster at 4.77 eV results in electron transfer from the iodide moiety to the uracil, creating a valence-bound (VB) anion within the cross-correlation of the pump and probe laser pulses. This species can decay by a number of channels, including autodetachment and dissociation to I− or larger anion fragments. Comparison of the energetics of the photoexcited cluster and its decay dynamics with those of the bare iodide-uracil (I−·U) complex provide a sensitive probe of the effects of microhydration on these species.