title: Mechanism of O((3)P) formation from a hydroxyl radical pair in aqueous solution.
abstract: The reaction mechanism for the rapid formation of a triplet oxygen atom, O((3)P), from a pair of triplet-state hydroxyl radicals in liquid water is explored utilizing extensive Car-Parrinello MD simulations and advanced visualization techniques. The local solvation structures, the evolution of atomic charges, atomic separations, spin densities, electron localization functions, and frontier molecular orbitals, as well as free energy profiles, evidence that the reaction proceeds through a hybrid (hydrogen atom transfer and electron-proton transfer) and hemibond-assisted reaction mechanism. A benchmarking study utilizing high-level ab initio calculations to examine the interactions of a hydroxyl radical pair in the gas phase and the influence of a hemibonded water is also provided. The results presented here should serve as a foundation for further experimental and theoretical studies aimed at better understanding the role and potential applications of the triplet oxygen atom as a potent reactive oxygen species.
authors.forename: Edelsys
authors.initials: E
authors.lastname: Codorniu-Hernández
authors.forename: Kyle Wm
authors.initials: KW
authors.lastname: Hall
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry, University of Graz , Heinrichstraße 28/IV, 8010 Graz, Austria.|Department of Chemistry, University of Potsdam , Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany.
authors.forename: A Daniel
authors.initials: AD
authors.lastname: Boese
authors.forename: Daniel
authors.initials: D
authors.lastname: Ziemianowicz
authors.forename: Sheelagh
authors.initials: S
authors.lastname: Carpendale
authors.forename: Peter G
authors.initials: PG
authors.lastname: Kusalik