Stochastic modeling of partially diffusion-controlled reactions in spur kinetics

Stochastic simulation techniques have been developed for modeling partially diffusion-controlled reactions in spur kinetics. These methods have been used to examine whether deviation from full diffusion control influences the overall spur chemistry. Studies of idealized two-species spurs suggest that the time dependence of the kinetics is not affected by the nature of the reaction; however, the overall chemistry of a spur can be influenced by a deviation from full diffusion control as whether the reaction is fully or merely partially diffusion controlled can have a significant effect on the initial overlap of the reactants. The reaction at time zero, which depletes the yield of reactants, is determined by the relative values of the width of the spur and of the encounter radius. This depletion is of particular importance in the radiation chemistry of water where the spatial distribution of the hydroxyl radical in a spur is believed to be significantly tighter than the distribution of the hydrated electron.