Metal ion aqua complexes

Inert metal ion aqua complexes such as [Cr(NH3)5(OH2)] can accelerate the hydrolysis of phosphate esters. These species are believed to act as a general base catalyst. On the other hand, CrOj inhibits the enzyme action of phosphatase and sulfatase and the inhibitary action is enhanced by the addition of phenol. Certain Cr(III) complexes can also act as catalysts in the electrocatalytic reduction of CO2 to MeOH, but they are not as efficient as iron complexes. 

To reveal the effect of the rate of chemical steps, we consider concentration profiles simulated for the certain model system. To make the mathematics simpler, we explore only a hmited number of components emphasizing that an increase in their number has no effect on general conclusions. Thus, the system to be analyzed would contain only free metal ions (aqua complexes) M", monoUgand complexes ML , and uncharged Ugand L. Then, a single chemical reaction Eq. (3.16) occurs both in the bulk of solution and in the 5-thick diffusion layer. 

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