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  • Time-resolved radiation chemistry: femtosecond photoelectron spectroscopy of electron attachment and photodissociation dynamics in iodide–nucleobase clusters
Title: Time-resolved radiation chemistry: femtosecond photoelectron spectroscopy of electron attachment and photodissociation dynamics in iodide–nucleobase clusters
Iodide–nucleobase (I − ·N) clusters studied by time-resolved photoelectron spectroscopy (TRPES) are an opportune model system for examining radiative damage of DNA induced by low-energy electrons. By initiating charge transfer from iodide to the nucleobase and following the dynamics of the resulting transient negative ions (TNIs) with femtosecond time resolution, TRPES provides a novel window into the chemistry triggered by the attachment of low-energy electrons to nucleobases. In this Perspective, we examine and compare the dynamics of electron attachment, autodetachment, and photodissociation in a variety of I − ·N clusters, including iodide–uracil (I − ·U), iodide–thymine (I − ·T), iodide–uracil–water (I − ·U·H 2 O), and iodide–adenine (I − ·A), to develop a more unified representation of our understanding of nucleobase TNIs. The experiments probe whether dipole-bound or valence-bound TNIs are formed initially and the subsequent time evolution of these species. We also provide an outlook for forthcoming applications of TRPES to larger iodide-containing complexes to enable the further investigation of microhydration dynamics in nucleobases, as well as electron attachment and photodissociation in more complex nucleic acid constituents.  more » « less
Award ID(s):
1663832
PAR ID:
10299681
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
21
Issue:
14
ISSN:
1463-9076
Page Range / eLocation ID:
7239 to 7255
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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