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Ionic criticality : an exactly soluble model

Jean-Noel Aqua·Michael E. Fisher
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Abstract

Gas-liquid criticality in ionic fluids is studied in exactly soluble spherical models that use interlaced sublattices to represent hard-core \textit{multi}component systems. Short range attractions in the uncharged fluid drive criticality but charged ions do not alter the universality class. Debye screening remains exponential \textit{at} criticality in charge-symmetric 1:1 models. However, \textit{asymmetry} couples charge and density fluctuations in a direct manner: the charge correlation length then diverges precisely as the density correlation length and the Stillinger-Lovett rule is violated \textit{at} criticality.

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Jean-Noel Aqua, Michael E. Fisher. 2003-11-20. Ionic criticality : an exactly soluble model. https://doi.org/10.1103/physrevlett.92.135702

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