mixed potential

The value of the potential of a given electrode with respect to a suitable reference electrode when appreciable contributions to the total anodic and/or cathodic partial currents are made by species belonging to two or more different couples, but the total current is zero, i.e.
I = ∑ i I i = 0 ( I i ≠ 0 )
where I i is the partial current of reaction i
I i = I i , a + I i , c
Source:
PAC, 1974, 37, 499 (Electrochemical nomenclature) on page 513