Water-structure based mechanistic view on the bimolecular decay of the hydrated electron

Abstract

The reaction between hydrated electrons (e−aq) is postulated to occur via proton transfer when electrons occupy neighbouring cavities in HB network. Subsequent recombination of a spatially correlated pair (H•, e−aq) leading to the formation of H2 is specific to backward scattering in rigid HB network stiffen by the presence of supramolecular structures of continuously connected four-bonded molecules. Disappearance of backward scattering between 150 and 200°C favours dissociation of (H•, e−aq). The postulated mechanism explains slower decay of e−aq in alkaline hydrogenated solutions above 150°C.