A kinetic study of some ligand substitution reactions

The rate constant for the formation and dissociation of the one-to-one complexes of nickel with malonate and succinate ligands and magnesium with oxalate ligand have been determined by a pressure-jump technique. The rates were determined at different temperatures and the activation parameters calculated. The results indicate that within experimental error there is no change in the activation parameters resulting from a change in properties of the ligand and they are consistent with a model in which the rate-determining step is the elimination of a water molecule from the inner hydration shell of the metal ion.