Geminate Recombination in the Presence of Scavengers: The New Vision of the Old Problem

A geminate reaction between and reactants affected by the bulk reaction between and scavengers is discussed. The exact solution of the problemobtained recently for randomly walking reactant (excess electron) is comparedwith the superposition approximation commonly used to interpret experimentaldata. Distinctions related to the important role of time correlations between geminateand bulk reactions are analyzed. The largest deviations exponentially growingin time are observed for geminate reaction rate in the presence of scavengers. Itis shown that superposition approximation can decrease essentially the ultimateprobability of geminate recombination. The difference is great enough to lead toqualitatively incorrect description of the experiment even at small concentration ofscavengers. This, in turn, may give rise to considerable errors in the determinationof geminate pair parameters or, alternatively, to the wrong information about bulkkinetics of electron scavenging