Solvent excess entropy at the electrode—solution interface

A model for water molecules in the double layer based upon information from gas-phase adsorption measurements has been used to calculate the configurational entropy of water in the double layer as a function of electric charge. The calculations agree well experimentally both in respect to dependence on charge and particularly in the position of the maximum entropy. The model can also be made consistent with the rest of the solvent excess entropy. The consistency between model and experiment favours models of capacitance humps which are not dependent upon water molecule orientation.