NONUNIFORMITY WINDOWS AT THE OXIDE AQUEOUS INTERFACE, APPARENT PROTON-TRANSFER RATES IN PH-JUMP RELAXATION KINETICS/

A pH-jump relaxation technique was developed for the investigation of proton transfer processes taking place at the oxide/aqueous interface. This approach is possible within narrow windows of equilibrium surfac e nonuniformity as revealed by the sample's proton affinity distributi on (PAD). Within a restricted domain of the observed relaxation spectr um, a simple kinetic model coupled with appropriate charge balance all ows for the determination of apparent kinetic constants of proton bind ing/release. This approach provides an independent estimate of the equ ilibrium constant which coincides with the mean PAD value of the speci fic nonuniformity domain.