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Title: Oscillatory surface forces: A test of the superposition approximation

Journal Article · · Journal of Chemical Physics
DOI:https://doi.org/10.1063/1.472150· OSTI ID:288833
;  [1]
  1. Computational Materials Department, Sandia National Laboratories, Albuquerque, New Mexico 87185-1111 (United States)

We report on the density functional theory calculations of electrolyte solutions confined between charged plates. Experiments with the surface forces apparatus have shown that for charged cylinders in simple solvents the surface force is oscillatory at short range. It has been suggested that the total force be considered a superposition of the electrostatic repulsion, the solvation force of a pure solvent, and the van der Waals attraction. In this paper we use the Rosenfeld{endash}Kierlik{endash}Rosinberg (RKR) functional to study a three-component electrolyte solution and explicitly test the superposition approximation. We find that the superposition approximation is a good approximation when the surface charge is low and the salt concentration is high. We also find that a three-component electrolyte can display short-range equilibrium separations in the absence of van der Waals interactions. {copyright} {ital 1996 American Institute of Physics.}

Research Organization:
Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA (United States)
DOE Contract Number:
AC04-94AL85000
OSTI ID:
288833
Journal Information:
Journal of Chemical Physics, Vol. 105, Issue 7; Other Information: PBD: Aug 1996
Country of Publication:
United States
Language:
English