A model for proton-assisted electron transfer

Proton-assisted electron transfer is a little studied but interesting possi bility for long-range electron transfer in systems where several substructu res are packed together by hydrogen bonds. The mechanism operates as follow s. An electron is fed to an acceptor molecule A; the protons of the H-bond chain which connects A to another redox site D move in the direction of the extra negative charge, localizing the negative charge on D; D releases an electron to an outer electron acceptor group; the reverse shift of the H-bo nd protons carrying an electron restores the original situation. (C) 1999 E lsevier Science B.V. All rights reserved.