Diagnostic Criteria to Identify a Reversible Process

For any process the ratio between the current of the reverse peak and that of the forward peak, /pr//pf, is particularly important. This current ratio is the parameter which allows one to judge the chemical reversibility of an electrode reaction. In fact, when such a ratio is equal to 1, the electrogenerated species Red is stable (at least on the cyclic voltammetric timescale). The /pr//pf ratio is easily calculated in computerized instrumentation or must be determined graphically in 

This relationship is particularly useful when the forward peak is accompanied by successive peaks at a distance which inhibits a good baseline from being drawn for the reverse peak. In this case, the automatic data given by computerized apparatus may not be completely reliable. 

Returning now to the diagnostic criteria for a reversible process, they can be subdivided as follows. 

It means that, for reversible one-electron processes, the peak-to-peak separation assumes different values as a function of the temperature namely  

Similar to the current ratio, the peak-to-peak separation AEp is another important parameter in that it relates to the electrochemical 

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