Fourth Moment Sum Rule for the Charge Correlations of a Two-Component Classical Plasma
| Autor: | Riccardo Fantoni, Angel Alastuey |
|---|---|
| Přispěvatelé: | Laboratoire de Physique de l'ENS Lyon (Phys-ENS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica, Università di Trieste, National Institute for Theoretical Physics (NITheP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Università degli studi di Trieste = University of Trieste |
| Rok vydání: | 2016 |
| Předmět: |
Physics
Critical behaviours Statistical Mechanics (cond-mat.stat-mech) Charge correlations Two-component plasmas FOS: Physical sciences Ionic bonding Charge density Statistical and Nonlinear Physics Plasma Electrostatic induction 01 natural sciences 010305 fluids & plasmas Critical point (thermodynamics) Sum rules Quantum mechanics 0103 physical sciences Compressibility Density functional theory Sum rule in quantum mechanics [PHYS.COND.CM-SM]Physics [physics]/Condensed Matter [cond-mat]/Statistical Mechanics [cond-mat.stat-mech] 010306 general physics Condensed Matter - Statistical Mechanics Mathematical Physics |
| Zdroj: | Journal of Statistical Physics. 163:887-913 |
| ISSN: | 1572-9613 0022-4715 |
| Popis: | We consider an ionic fluid made with two species of mobile particles carrying either a positive or a negative charge. We derive a sum rule for the fourth moment of equilibrium charge correlations. Our method relies on the study of the system response to the potential created by a weak external charge distribution with slow spatial variations. The induced particle densities, and the resulting induced charge density, are then computed within density functional theory, where the free energy is expanded in powers of the density gradients. The comparison with the predictions of linear response theory provides a thermodynamical expression for the fourth moment of charge correlations, which involves the isothermal compressibility as well as suitably defined partial compressibilities. The familiar Stillinger-Lovett condition is also recovered as a by-product of our method, suggesting that the fourth moment sum rule should hold in any conducting phase. This is explicitly checked in the low density regime, within the Abe-Meeron diagrammatical expansions. Beyond its own interest, the fourth-moment sum rule should be useful for both analyzing and understanding recently observed behaviours near the ionic critical point. |
| Databáze: | OpenAIRE |
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