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Screening in Yukawa fluid mixtures

A. J. Archer·P. Hopkins·R. Evans
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Abstract

The effective pair potential between mesoscopic charged particles in a neutralising background medium takes a Yukawa form $\exp(-λr)/r$ with screening length $λ^{-1}$. We consider a dilute suspension of such Yukawa particles dispersed in a solvent with correlation length $ξ<λ^{-1}$ and show that the Yukawa interaction is `screened' if the pair potentials between solvent particles exhibit Yukawa decay with the same screening length $λ^{-1}$. However, if the solvent pair potentials are shorter ranged than the solute Yukawa potentials, then the effective potential between pairs of solute particles is `unscreened', i.e. the effective potential between the solute particles is equal to the bare potential at large particle separations.

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A. J. Archer, P. Hopkins, R. Evans. 2006-06-28. Screening in Yukawa fluid mixtures. https://doi.org/10.1103/physreve.74.010402

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