Title | Forces between like-charged plates in electrolyte solution: Ion-solvent packing versus electrostatic effects |
Publication Type | Journal Article |
Year of Publication | 1999 |
Authors | Otto, F, Patey, GN |
Journal | Physical Review E |
Volume | 60 |
Pagination | 4416-4422 |
Date Published | Oct |
Type of Article | Article |
ISBN Number | 1063-651X |
Keywords | ELECTRICAL DOUBLE-LAYER, IMAGE, INHOMOGENEOUS COULOMB FLUIDS, interactions, MOLECULAR THEORY, NARROW SLITS, PLANAR SURFACES, SIMULATIONS, SOLVATION FORCES |
Abstract | The anisotropic hypernetted-chain approximation is solved numerically for mixtures of neutral hard-sphere solvent particles and divalent counterions between charged plates. A detailed analysis of the different components of force acting between the plates is given. At separations of a few solvent diameters, it is shown that even at relatively high surface charge and moderate solvent density, the ionic contribution to the force tends to be dominated by the hard-core or packing component. If the ions and solvent particles are of equal size, then the net pressure between the plates can be reasonably well approximated by adding the pressures of pure one-component ionic and solvent systems. However, if the ion and solvent diameters are significantly different the pressure curve is more complex, and the simple superposition of the ionic and solvent pressures no longer works. For this case, we show that to a good approximation it is still possible to divide the pressure into electrostatic and hard-core components, but now the appropriate hard-core system must itself be a mixture of neutral hard spheres. [S1063-651X(99)08210-0]. |
URL | <Go to ISI>://000083414900025 |
