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arXiv · 1208.0693

Closed-loop liquid-vapor equilibrium in a one-component system

N. G. Almarza
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Abstract

We report Monte Carlo simulations that show closed-loop liquid-vapor equilibrium in a pure substance. As far as we know, this is the first time that such a topology of the phase diagram has been found for one-component systems. This finding has been achieved on a two-dimensional lattice model for patchy particles that can form network fluids. We have considered related models with a slightly different patch distribution in the order to understand the features of the distribution of patches on the surface of the particles that make possible the presence of the closed-loop liquid-vapor equilibrium, and its relation with the phase diagram containing the so-called empty liquids. Finally we discuss the likelihood of finding the closed-loop liquid-vapor equilibria on related models for three dimensional models of patchy particles in the continuum, and speculate on the possible relationship between the mechanism behind the closed-loop liquid vapor equilibrium of our simple lattice model and the salt-induced reentrant condensation found in complex systems.

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N. G. Almarza. 2012-08-03. Closed-loop liquid-vapor equilibrium in a one-component system. https://doi.org/10.1103/physreve.86.030101

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