Ligands ligand-field, redox potential correlation

Correlations have been made between gas-phase ionization potentials of free ions and the redox potentials of isostructural [MXe]"" complexes of the elements of the same row of the periodic table (476). Despite the observation of such correlations, caution must be taken, because they ignore both cr and tt ligand field effects. The latter are often more important in influencing the relative oxidizing or reducing strength of complexes. 

Under appropriate conditions, analysis of cychc voltanuno-grams such as that shown in Figure 1 provide simple measures of the solution redox potentials of transition metal complexes, derived as 1/2. Extensive tabulations of redox potentials are available, and provide a key resource for inorganic chemistry. The correlation redox potentials with parameters such as ligand field strength, ligand hardness, and ionization energy of the transition metal forms an important theoretical framework for transition metal chemistry. 

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