title: Density dependence of the yield of hydrated electrons in the low-LET radiolysis of supercritical water at 400 °C: influence of the geminate recombination of subexcitation-energy electrons prior to thermalization.
abstract: Monte Carlo simulations were used to calculate the yield of hydrated electrons (eaq(-)) in the low-linear energy transfer radiolysis of supercritical water at 400 °C as a function of water density over the range of ~0.15 to 0.6 g cm(-3). Very good agreement was found between our calculations and picosecond pulse radiolysis experimental data at ~60 ps and 1 ns at high density (>0.35 g cm(-3)). At densities lower than ~0.35 g cm(-3), our eaq(-) yields were lower than the experimental data, especially at ~60 ps. However, if we incorporated into the simulations a prompt geminate electron-cation (H2O˙(+)) recombination (prior thermalization of the electron) that decreased as the density decreased, our computed eaq(-) yields at ~60 ps and 1 ns compared fairly well with the experimental data for the entire density range studied.
authors.affiliation: Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, 3001, 12ème Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada. jean-paul.jay-gerin@USherbrooke.ca.
authors.forename: Jintana
authors.initials: J
authors.lastname: Meesungnoen
authors.forename: Sunuchakan
authors.initials: S
authors.lastname: Sanguanmith
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Jay-Gerin
mesh_terms: D004583:Electrons; D006358:Hot Temperature; D009010:Monte Carlo Method; D011675:Pulse Radiolysis; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water