Unequal size of ions in modified Wicke-Eigen model of electric double layer.

Numerous electric double layer models have been developed through the years to capture the complex electrode/electrolyte interface. In the present study, the Wicke-Eigen model of electric double layer is generalized to incorporate the asymmetric size of cations and anions. Analytical expressions for the spatial distribution of ions and water dipoles are derived. Asymmetric and symmetric Wicke-Eigen models are analysed. Arguments are given in favour of changing the recently adopted name of so-called Bikerman model/equation to Wicke-Eigen model/equation.