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arXiv · 1207.3274

On the contact values of the density profiles in an electric double layer using density functional theory

L. B. Bhuiyan·D. Henderson·S. Sokołowski
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Abstract

A recently proposed local second contact value theorem [Henderson D., Boda D., J. Electroanal. Chem., 2005, 582, 16] for the charge profile of an electric double layer is used in conjunction with the existing Monte Carlo data from the literature to assess the contact behavior of the electrode-ion distributions predicted by the density functional theory. The results for the contact values of the co- and counterion distributions and their product are obtained for the symmetric valency, restricted primitive model planar double layer for a range of electrolyte concentrations and temperatures. Overall, the theoretical results satisfy the second contact value theorem reasonably well, the agreement with the simulations being semi-quantitative or better. The product of the co- and counterion contact values as a function of the electrode surface charge density is qualitative with the simulations with increasing deviations at higher concentrations.

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L. B. Bhuiyan, D. Henderson, S. Sokołowski. 2012-07-13. On the contact values of the density profiles in an electric double layer using density functional theory. https://doi.org/10.5488/cmp.15.23801

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