Metals metallic electrons

When metallo-enzymes effect the oxidation or rednction of organic snbstrates or simple molecules such as H2O, N2 or O2, they often function as multielectron donors or acceptors with two or more metals at the active The electronic conpUng between the metals is often accompanied by uniqne spectroscopic features such as electron spin spin coupling. The metal metal electronic coupling may facilitate the multi-electron-transfer reactions with the snbstrates. In simpler molecular systems, two electron-transfer processes most often reqnire snbstrate binding , as in an inner-sphere, gronp (or atom ) transfer process. ... 

There is electron hopping between the redox centers (process 1), as in conventional redox polymers. Electron transfer may also occur through the polymer backbone via a metal-metal electronic interaction (process 2, superexchange pathway) or via polymer-based charge carriers (process 3, polymer mediation). The electronic interactions between the tt-system of the polymer and the metal centers usually enhance the rate of the electron transfer process. Electron transfer via polymer-based charge carriers requires the polymer to be electronically conductive at potentials close to the formal potential of the redox groups. 

A review on pulse radiolysis contains references to a number of intriguing metal-metal electron-transfer reactions with relatively unfamiliar reagents such as Zn+, Cd+, and Ag . ... 

In this section we review most of the new experimental data on metal-metal electron transfer reactions in solution, in which the rate law for the primary process (19) can be expressed in the second-order form (20), or in related forms explicable in terms of... 

ORGANOMETALLIC CONDUCTIVE POLYMERS WITHOUT INTRINSIC INTRACHAIN METAL-METAL ELECTRONIC INTERACTION (NON-CONJUGATED SYSTEM)... 

OCPs without intrinsic interchain metal-metal electronic interaction, e.g., poly(vinylferrocene)... 

As in the previous volume, an attempt has been made to include all work on the kinetics or mechanisms of metal-metal electron-transfer reactions published during the period under review, though for reasons of space some of the references are limited to entries in the Tables, which are collected together at the end of the chapter. A few of the journals for 1977 were still not available at the time of writing, but will be dealt with in the next volume. 

Various reducible organic molecules have been found to be effective catalysts for metal-metal electron-transfer reactions, though (contrary to some suggestions ) they do not necessarily act as bridges in any structural sense. The general mechanism is equations (77) and (78), where A = [Co(NH3)e] +, [Co(en)3] +, or various... 

Gusev DG, Peris E. The Tolman electronic parameter (TEP) and the metal-metal electronic communication in ditopic NHC complexes. Dalton Trans. 2013 42 7359-7364. 

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