Specific Oxidants and Reductants

Consideration of Specific Oxidants and Reductants.— In this section systems in which one or both of the metal ions involved is the centre of attention are described. 

A review on the resonance Raman effect contains some other references to electron-transfer systems, notably Pt -Pt compounds.  

Cobalt(ni). Using the specially synthesized ligands shown in formulae (16) and (17), two cobalt(iii) complexes have been prepared, with tertiary N or thioetherS 

Reduction of the N-bonded glycinatopenta-amminecobalt(in) complex by Cr + yields 0-bonded glycinatopenta-aquochromium(iii), indicating a remote attack mechanism. The rate law is 

Reactions of cobalt complexes of macrocyclic tetramine ligands with various couples (including the highly oxidizing MnCl /, hitherto little studied) have been reported. Inner-sphere and outer-sphere reactions involving, for example, [Ru(NH3)6py] +/ + have been characterized. A free-energy correlation for reactions between [Co(N4)(OH2)2] with inner-sphere oxidants shows the expected slope 9AG /3AG 0.5 down to a limit of AG a 7 kcal mol, which is believed to represent diffusion control. Application of the Marcus equations (1) and (3) to reactions of both types leads to an assessment of the factors con- 

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Estimation of rates for redox reactions in environmental systems requires that the problem be formulated in terms of specific oxidation and reduction half-reactions. In addition, we assume that the rate-limiting step of the transformation mechanism is bimolecular—that is, the slow step requires an encounter (collision) between the electron donor and electron acceptor. Under most conditions found in environmental systems, such reactions exhibit rate laws for the disappearance of a pollutant, P, that are first-order in concentration of P and first-order in the concentration of environmental oxidant or reductant, E,... 

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