title: Ionic criticality: an exactly soluble model.
abstract: Gas-liquid criticality in ionic fluids is studied in exactly soluble spherical models that use interlaced sublattices to represent hard-core multicomponent systems. Short-range attractions in the uncharged fluid drive criticality, but charged ions do not alter the universality class. Debye screening remains exponential at criticality in fully ion-symmetric 1:1 models. However, ionic 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 at criticality.
authors.affiliation: Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: Jean-Noël
authors.initials: JN
authors.lastname: Aqua
authors.forename: Michael E
authors.initials: ME
authors.lastname: Fisher