The IUPAC definition of electrokinetic parameters

The International Union of Pure and Applied Chemistry (IUPAC) has given general definitions of the electrochemical paramenters as follows [8, 9], 

Identity (150) only holds if the same step remains rate-controlling over the wide range of potentials involved. As seen in Sect. 4.1, this condition is not very realistic in complex multistep electron transfer electrode reactions. 

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