Aqua Jean-Noël, Fisher Michael E
Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA.
Phys Rev Lett. 2004 Apr 2;92(13):135702. doi: 10.1103/PhysRevLett.92.135702.
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.
在使用交错子晶格来表示硬核多组分系统的完全可解球形模型中，研究了离子液体中的气液临界性。中性流体中的短程吸引力驱动着临界性，但带电离子不会改变普适类。在完全离子对称的1:1模型中，德拜屏蔽在临界时仍保持指数形式。然而，离子不对称以直接的方式耦合了电荷和密度涨落：电荷关联长度随后精确地随着密度关联长度发散，并且在临界时违反了斯蒂林格-洛维特规则。
