Ionic fluid criticality lattice theories

Concerning the fluid some possibilities for tricriticality are discussed. The GDH theory predicts an order-transition between the isotropic fluid and a phase with periodic charge density waves [94], The corresponding transition line cuts the liquid-liquid line near their critical point, so that a tricritical point is a possibility. The possible presence of both, gas-liquid and tricritical points in ionic fluids has been predicted by Ciach and Stell [96] for a model, in which additional short-range forces supplement the lattice Coulomb forces. 

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