Manifestations of the Esin-Markov effect in the Grahame-Parsons and the Alekseev-Popov-Kolotyrkin models

Dependences of (a) zero-charge potential E-q (=) (0) on the logarithm of co ncentration c of a salt with a surface-active anion and (b) the surface exc ess of cations Gamma(+), on the electrode charge q in the region q > 0 are analyzed. The analysis is based on model calculations and experimental data available from literature. It is shown that, despite the commonly adopted view, the fact that the conditions (partial derivative Gamma(+)/partial der ivative q)c less than or equal to 0 or \dE(q=0)/dln c\ less than or equal t o RT/F are fulfilled is insufficient to prove the absence of the Esin-Marko v effect in a system.