Electron, proton, and energy transfer

R. A. Wheeler, in R. A. Wheeler (Ed.). Bioenergetics of Electron, Proton, and Energy Transfer. ACS Sympsium Series, Washington DC, 2000, Submitted. 

Introduction to the Molecular Bioenergetics of Electron, Proton, and Energy Transfer... 

Molecular bioenergetics simulations of electron, proton, and energy transfer / Ralph A. Wheeler, editor sponsored by the ACS Division of Computers in Chemistry. 

A variety of thermochemical data were obtained for negatively charged metal complexes. For example, appearance energy measurements photodissociation, energy-resolved, collision-induced dissociation, electron-, proton- and anion-transfer reactions to and from negatively charged ions, were all used for obtaining a variety of thermochemical parameters for ions, molecules, and radicals. 

The effects of photophysical intermolecular processes on fluorescence emission are described in Chapter 4, which starts with an overview of the de-excitation processes leading to fluorescence quenching of excited molecules. The main excited-state processes are then presented electron transfer, excimer formation or exciplex formation, proton transfer and energy transfer. 

In the gas phase the proton is a tremendous acceptor of electron density, and the transfer energy is very large. This transfer energy has already been largely "spent" for the solvated prnton (e.g.. hydronitim ion) in solution where the reactions are of si displacement type ... 

Based on these results of model electron and energy transfer reactions MPT must produce superoxide by both direct (Equation 23), as well as proton assisted transfer (Equation 24). 

Electrochemical and photochemical processes are the most convenient inputs and outputs for interfacial supramolecular assemblies in terms of flexibility, speed and ease of detection. This chapter provides the theoretical background for understanding electrochemical and optically driven processes, both within supramolecular assemblies and at the ISA interface. The most important theories of electron and energy transfer, including the Marcus, Forster and Dexter models, are described. Moreover, the distance dependence of electron and energy transfer are considered and proton transfer, as well as photoisomerization, are discussed. 

Photostimulated molecular motion is an important photophysical phenomenon frequently exploited in molecular switches. The molecular electronic rearrangements accompanying optical excitation may stimulate nuclear rearrangement of the excited species. Like electron and energy transfer, such processes compete with radiative events and therefore reduce the measured lifetime and quantum yield of emission. The most important nuclear rearrangements in supramolecular species are proton transfer and photoisomerization. 

Bregadze V, Kutsishvili I, Chkhaberidze J, Sologashvili K. DNA as a mediator for proton, electron and energy transfer induced by metal ions. Inorg Chim Acta 2002 339 145-59. 

There are many photophysical processes that are responsible for the de-excitation of molecules. The few examples of intermolecular photophysical processes that induce fluorescence quenching are electron transfer, proton transfer and energy transfer. The following section will focus on energy transfer and most specifically on nonradiative energy transfer. 

Jiminez, M. C., Leal, R, Miranda, M. A., and Tormos, R., Chemical evidence for intramolecular proton, electron and energy transfer in the photochemistry of o-allylphenol derivatives, J. Org. 

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