Molybdenum, octacyanides

The substances K8Re(CN)8 and K8Re(CN)8, recently reported,74 probably contain Re(V) and Re(VI) with ligancy 8 and the same configuration as the molybdenum octacyanide complexes. 

Because of their properties they are widely used in electrochemistry, in electrophotography, as well as in photocatalysis and photochemical water cleavage. Thus Hennig and Rehorek in 1986 reported the sensitization of photochemical reactions by Prussian blue analogues of molybdenum octacyanide, and Kaneko and his group in 1984 found that water can be photolyzed with visible light in presence of Pmssian blue and tris (2, 2 -bipyridine) ruthenium (II) complex. 

Micellar Efllecls on Inorganic Reactions.—Electron transfer between ferric ion and phenothiazine is inhibited by cationic micelles and accelerated by up to 10 -fold in anionic micelles of sodium lauryl sulphate. " In both cases the rate-surfactant concentration profile can be simulated accurately. Anionic micelles only cause a small effect on the reactivity of ruthenium(iii) tris(bipyridyl) with molybdenum(iv) octacyanide but accelerate the reaction between ferrous ion and tris(tetramethylphenanthroline)iron(ra). In the latter case a plot of surfactant concentration is linear with the reciprocal of the observed rate constant. Fast outer-sphere electron-transfer reactions may decrease in rate constant by up to four orders of magnitude when one of the reactants is solubilized in an anionic micelle. When this partner is neutral the inhibition is reduced somewhat by added salt, but when it is cationic the effect may be attenuated by competitive binding of Na or HsO and exclusion of reactant from the micelle. Oxidation of diethyl sulphide is catalysed by micelles of sodium lauryl sulphate containing carboxylate-ions by the mechanism shown. (Scheme 3). The rate advantage is quantitatively accounted for by the entropy term, and hexanoate is forty-fold more effective than acetate. Electron-transfer between the anionic trans-1,2-diaminocyclohexane... 

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