Substitution reactions crystal field theory

Much of the data now available on the substitution of coordinated water from hydrated metal ions are summarized in Fig. 14. The results show the expected dependence on electrostatic factors, since a small ionic charge and/or a large ionic size favors a fast reaction. For the first row transition ions it is noteworthy that exchange is slowest for the d system Ni(II), as is predicted by the crystal field theory. The unusually rapid exchanges for Cu(II) and Zn(II) may be the consequence of their not having a regular octahedral structure. 

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