Dissociative ligand substitution reactions aqua ions

Prior to the advent of variable pressure 0 n.m.r. studies of solvent exchange in the aqua ions of V(II) to Ni(II) it had generally been accepted that the complex formation reactions on all octahedral divalent ions proceeded via Ij mechanisms. However, it now appears that for the early members of the series the associative I, mechanism becomes important with the reactions showing a small dependence on the entering ligand L. The usual Eigen Wilkins approach still appears to be effective as a predictive tool for rationalising the rates of both dissociative and associative I, substitution reactions in these cases. 

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