Liquid-Liquid Phase Transition for an Attractive Isotropic Potential with Wide Repulsive Range
arXiv:cond-mat/0412159 · doi:10.1103/PhysRevE.71.061504
Abstract
Recent experimental and theoretical results have shown the existence of a liquid-liquid phase transition in isotropic systems, such as biological solutions and colloids, whose interaction can be represented via an effective potential with a repulsive soft-core and an attractive part. We investigate how the phase diagram of a schematic general isotropic system, interacting via a soft-core squared attractive potential, changes by varying the parameters of the potential. It has been shown that this potential has a phase diagram with a liquid-liquid phase transition in addition to the standard gas-liquid phase transition and that, for a short-range soft-core, the phase diagram resulting from molecular dynamics simulations can be interpreted through a modified van der Waals equation. Here we consider the case of soft-core ranges comparable with or larger than the hard-core diameter. Because an analysis using molecular dynamics simulations of such systems or potentials is too time-demanding, we adopt an integral equation approach in the hypernetted-chain approximation. Thus we can estimate how the temperature and density of both critical points depend on the potential's parameters for large soft-core ranges. The present results confirm and extend our previous analysis, showing that this potential has two fluid-fluid critical points that are well separated in temperature and in density only if there is a balance between the attractive and repulsive part of the potential. We find that for large soft-core ranges our results satisfy a simple relation between the potential's parameters.
References in corpus (20)
- Extended corresponding-states behavior for particles with variable range attractions
- Generic mechanism for generating a liquid-liquid phase transition
- Core-softened potentials and the anomalous properties of water
- Computer simulations of liquid silica: equation of state and liquid-liquid phase transition
- Phase behavior of a system of particles with core collapse
- Liquid State Anomalies for the Stell-Hemmer Core-Softened Potential
- Liquid-Liquid Phase Transitions for Soft-Core Attractive Potentials
- Intra-molecular coupling as a mechanism for a liquid-liquid phase transition
- Metastable liquid-liquid phase transition in a single-component system with only one crystal phase and no density anomaly
- Liquid-liquid equilibrium for monodisperse spherical particles
- Water-Like Anomalies for Core-Softened Models of Fluids: Two-Dimensional Systems
- Physics of the liquid-liquid critical point
- Water-like anomalies for core-softened models of fluids: One dimension
- Exotic fluids and crystals of soft polymeric colloids
- Applications of the Stell-Hemmer Potential to Understanding Second Critical Points in Real Systems
- Density anomaly in a competing interactions lattice gas model
- Density Anomaly in Core-Softened Lattice Gas
- Simple Fluids with Complex Phase Behavior
- Structural transitions and nonmonotonic relaxation processes in liquid metals
- A Finite-Size Scaling Study of a Model of Globular Proteins
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- Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids
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- Water-like hierarchy of anomalies in a continuous spherical shouldered potential
- Structural anomalies for a three dimensional isotropic core-softened potential
- Metastable liquid-liquid coexistence and density anomalies in a core-softened fluid
- Isotropic soft-core potentials with two characteristic length scales and anomalous behaviour
- Softness dependence of the Anomalies for the Continuous Shouldered Well potential
- A System with Multiple Liquid-Liquid Critical Points
- Thermodynamics of Fluid Polyamorphism
- The physics of Empty Liquids: from Patchy particles to Water
- Relation between the Liquid-Liquid Phase Transition and Dynamic Behavior in the Jagla Model
- Structural behavior and dynamics of an anomalous fluid between solvophilic and solvophobic walls: templating, molding and superdiffusion
- Thermodynamic and Dynamic Anomalies for Dumbbell Molecules Interacting with a Repulsive Ramp-Like Potential
- Generalized van der Waals theory of liquid-liquid phase transitions
- Waterlike anomalies in a 2D core-softened potential
- Liquid polymorphism and density anomaly in a three-dimensional associating lattice gas
- Enhanced flow of core-softened fluids through nanotubes
- Diffusion Anomaly in a three dimensional lattice gas
- Structural properties of fluids interacting via piece-wise constant potentials with a hard core
- Rational-function approximation for fluids interacting via piece-wise constant potentials
- Microscopic structure and thermodynamics of a core-softened model fluid from the second-order integral equations theory
- Relation between occupation in the first coordination shells and Widom line in Core-Softened Potentials
- Structural and thermodynamic properties of fluids whose molecules interact via one-, two-, and three-step potentials
- Discontinuous Structural Transitions in Fluids with Competing Interactions
- Possible phase transition in liquid Cesium at ambient pressure