Electron transfer, between metal ions

Blasse G (1991) Optical Electron Transfer Between Metal Ions and its Consequences. 76 153-188... 

Optical Electron Transfer Between Metal Ions... 

Electron transfer between metal ions contained in complexes can occur in two different ways, depending on the nature of the metal complexes that are present. If the complexes are inert, electron transfer occurring faster than the substitution processes must occur without breaking the bond between the metal and ligand. Such electron transfers are said to take place by an outer sphere mechanism. Thus, each metal ion remains attached to its original ligands and the electron is transferred through the coordination spheres of the metal ions. 

Various metal nitrates, represented by silver nitrate, sensitize photopolymerization of AN, methaciylonitrile, a-chloroacrylonitrile, croto-nitrile and methyl methacrylate. The efficiency of photosensitization runs nearly parallel to the ease of reduction of the metal ion. Although there is little doubt that the monomer plays some role in the photochemical process, it is rather difficult to decide whether the primary act is direct oxidation of the monomer or electron transfer between metal ion and nitrate anion. 

The rate-controlling step in reductive dissolution of oxides is surface chemical reaction control. The dissolution process involves a series of ligand-substitution and electron-transfer reactions. Two general mechanisms for electron transfer between metal ion complexes and organic compounds have been proposed (Stone, 1986) inner-sphere and outer-sphere. Both mechanisms involve the formation of a precursor complex, electron transfer with the complex, and subsequent breakdown of the successor complex (Stone, 1986). In the inner-sphere mechanism, the reductant... 

In aqueous solution outer-sphere electron transfer between metal ions and alkyl hydroperoxides [reactions (95) and (96)] is expected to be favorable. In nonpolar solvents, electron transfer probably proceeds via the formation of inner-sphere, covalently bonded complexes. The overall reaction constitutes a catalytic decomposition of the hydroperoxide into alkoxy and alkylperoxy radicals ... 

In electron transfer between metal ions, a metal-ion catalyst normally reacts by nonassociative activation, in which the species do not form long-lived binuclear intermediates. The catalytic process often can be rationalized by reactivity patterns e.g., the Cu catalyses of the oxidation "of V(III) by Fe(III). This catalysis by Cu occurs by outer-sphere mechanisms as in ... 

Halpem J. and Oigel L. E. (1960), The theory of electron transfer between metal ions in bridged systems , Z)Acm55. Faraday Soc. 29, 32 1. 

Electron transfer between metal ions may occur either as inner-sphere (is) or an outer-sphere (os) reaction, The first case involves a ligand exchange and the... 

Creutz, C., Taube, H., A Direct Approach to Measuring the Franck Condon Barrier to Electron Transfer between Metal Ions, J. Am. Chem. Soc. 1969, 91, 3988 3989. 

Regarding the TMS spectrum, the appearance of magnetic order is obviously due to the absorption of CO2. The most likely mechanism of CO2 uptake at this level is the migration of stick-shaped CO2 molecules in channels of ordered O defects [ 15]. CO2 seems to play a similar role as the absence of oxygen it blocks fast electron transfer between metal ions that inhibits magnetic fluctuations and helps form static long-range order of spins. 

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