Independent pairs and Monte-Carlo simulations of the geminate recombination of solvated electrons in liquid-to-supercritical water
- 14 October 2011
- journal article
- Published by Royal Society of Chemistry (RSC) in Physical Chemistry Chemical Physics
- Vol. 13 (46), 20806-20819
- https://doi.org/10.1039/c1cp21678c
Abstract
Independent pairs (IP) and Monte Carlo (MC) simulations are employed to model experimental femtosecond time-resolved pump–probe spectroscopic data on the geminate recombination dynamics of solvated electrons in liquid-to-supercritical water. The hydrated electron was created by two-photon ionization of the neat fluid with a total ionization energy of 9.3 eV. In both numerical approaches, the ejection length, 〈r0〉, (i.e. the distance from the ionization core, at which the electron is thermally and spatially localized) is used as the primary adjustable fitting parameter that can bring both model simulations into quantitative agreement with the ultrafast kinetic experiment. The influence of the thermodynamic conditions on the ejection length and on the recombination mechanism is discussed. Whereas in the compressed liquid associated with a high dielectric constant (ε ≥ 20), the electron recombines predominantly with the OH radical, the dissociative recombination via charge neutralization with the hydronium cation takes over at small dielectric constants (ε < 20). The importance of charge–dipole interactions for Monte-Carlo simulations of the recombination reactions of the hydrated electrons in the low-permittivity region is stressed.Keywords
This publication has 86 references indexed in Scilit:
- Ultrafast Geminate Recombination after Photodetachment of Aqueous HydroxideJournal of the American Chemical Society, 2010
- Scaled Polynomial Expression for Self-Diffusion Coefficients for Water, Benzene, and Cyclohexane over a Wide Range of Temperatures and DensitiesJournal of Chemical & Engineering Data, 2010
- Excited state dynamics of liquid water: Insight from the dissociation reaction following two-photon excitationThe Journal of Chemical Physics, 2007
- Pulse Radiolysis of Supercritical Water. 1. Reactions between Hydrophobic and Anionic SpeciesThe Journal of Physical Chemistry A, 2002
- M.DynaMix – a scalable portable parallel MD simulation package for arbitrary molecular mixturesComputer Physics Communications, 2000
- Ultrafast transient-absorption spectroscopy of the aqueous solvated electronThe Journal of Chemical Physics, 1993
- Solvated electrons: what is solvated?The Journal of Physical Chemistry, 1991
- Solvated electron structure in glassy matrixesAccounts of Chemical Research, 1981
- Dipole Moment of the OH Radical from the Stark Effect of Its Microwave SpectrumThe Journal of Chemical Physics, 1961
- The Kinetics of Activation—Diffusion Controlled Reactions in Solution. The Temperature Dependence of the Quenching of Fluorescence1,2Journal of the American Chemical Society, 1948