In most of the oxidation—reduction reactions involving net electron transfer which have been studied, the experimental results yield only second order rates, and thus reflect the barrier to bringing reactants together as well as that for the electron transfer act itself. Recent advances in synthetic procedures make it possible to measure as an intramolecular or first order process, net electron...

Molecular vibrations and electron-vibrational interactions are central to the control of biomolecular electron and energy-transfer rates. The vibrational control of molecular electron-transfer reactions by infrared pulses may enable the precise probing of electronic-vibrational interactions and of their roles in determining electron-transfer mechanisms. This type of electron-transfer rate contr...

A wide range of biological processes makes extensive use of electron-transfer reactions. Rigorous characterization of a biological electron-transfer reaction requires a combination of kinetic, thermodynamic, structural and theoretical methods. The rate of electron transfer from an electron donor to an electron acceptor through a protein is dependent on the difference in reduction potential of t...

Proton-coupled electron transfer (PCET) is an important mechanism for charge transfer in a wide variety of systems including biology- and materials-oriented venues. We review several areas where the transfer of an electron and proton is tightly coupled and discuss model systems that can provide an experimental basis for a test of PCET theory. In a PCET reaction, the electron and proton may tran...

Three types of oxidation-reduction (redox) centers are found in biology: protein side chains, small molecules, and redox cofactors. The first class is frequently overlooked by mechanistic enzymologists. The sulfhydryl group of cysteine is easily oxidized to produce a dimer, known as cystine:-2e This type of interconversion is known to occur in several redox proteins, including xanthine oxidase,...

Recent investigations have shed much light on the nuclear and electronic factors that control the rates of long-range electron tunneling through molecules in aqueous and organic glasses as well as through bonds in donor-bridge-acceptor complexes. Couplings through covalent and hydrogen bonds are much stronger than those across van der Waals gaps, and these differences in coupling between bonded...