The role of water molecules in the dissociation of an electron-molecule contact pair

Clarke, Connor J.; Michi Burrow, E.; Verlet, Jan R. R.

Abstract

The hydrated electron, e–(aq), is a potent reducing agent and a prototypical quantum solute. Reactions of e–(aq) often involve a contact pair comprised of a molecule and electron that are hydrated within a single sphere. However, a molecular-level understanding of the solvent-driven coordinate that links the contact pair to the free dissociated e–(aq) remains elusive. Here, we study this coordinate by kinetically trapping representative metastable intermediates as gas-phase clusters and probing them using photoelectron spectroscopy. We apply this methodology to uracil-water anion clusters, where key intermediates are identified with supporting quantum chemical calculations. Just a single water molecule drives the parent molecule and non-valence electron apart, thereby inhibiting geminate recombination to form the more stable valence-bound uracil anion. The electron-water binding is akin to bare water cluster anions, highlighting the link to larger clusters and e–(aq). Our results provide a molecular-level view of quantum solute hydration and, more broadly, of how water-driven electron-transfer reactions proceed.

Citation

Clarke, C. J., Michi Burrow, E., & Verlet, J. R. R. (2025). The role of water molecules in the dissociation of an electron-molecule contact pair. Nature Communications, 16(1), Article 2113. https://doi.org/10.1038/s41467-025-57403-7

• Journal Article Type: Article
• Acceptance Date: Feb 18, 2025
• Online Publication Date: Mar 3, 2025
• Publication Date: Mar 3, 2025
• Deposit Date: Mar 10, 2025
• Publicly Available Date: Mar 10, 2025
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 16
• Issue: 1
• Article Number: 2113
• DOI: https://doi.org/10.1038/s41467-025-57403-7
• Public URL: https://durham-repository.worktribe.com/output/3699828