Low-Energy Shape Resonances of a Nucleobase in Water

Cooper, Graham A.; Clarke, Connor J.; Verlet, Jan R.R.

Abstract

When high-energy radiation passes through aqueous material, low-energy electrons are produced which cause DNA damage. Electronic states of anionic nucleobases have been suggested as an entrance channel to capture the electron. However, identifying these electronic resonances have been restricted to gas-phase electron-nucleobase studies and offer limited insight into the resonances available within the aqueous environment of DNA. Here, resonance and detachment energies of the micro-hydrated uracil pyrimidine nucleobase anion are determined by two-dimensional photoelectron spectroscopy and are shown to extrapolate linearly with cluster size. This extrapolation allows the corresponding resonance and detachment energies to be determined for uracil in aqueous solution as well as the reorganization energy associated with electron capture. Two shape resonances are clearly identified that can capture low-energy electrons and subsequently form the radical anion by solvent stabilization and internal conversion to the ground electronic state. The resonances and their dynamics probed here are the nucleobase-centered doorway states for low-energy electron capture and damage in DNA.

Citation

Cooper, G. A., Clarke, C. J., & Verlet, J. R. (2022). Low-Energy Shape Resonances of a Nucleobase in Water. Journal of the American Chemical Society, 145(2), 1319-1326. https://doi.org/10.1021/jacs.2c11440

• Journal Article Type: Article
• Acceptance Date: Oct 28, 2022
• Online Publication Date: Dec 30, 2022
• Publication Date: 2022
• Deposit Date: Jan 26, 2023
• Publicly Available Date: Jan 26, 2023
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 145
• Issue: 2
• Pages: 1319-1326
• DOI: https://doi.org/10.1021/jacs.2c11440