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arXiv · 1010.4676

Reentrant phase behaviour for systems with competition between phase separation and self-assembly

Aleks Reinhardt·Alexander J. Williamson·Jonathan P. K. Doye·Jesús Carrete·Luis M. Varela·Ard A. Louis
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Abstract

In patchy particle systems where there is competition between the self-assembly of finite clusters and liquid-vapour phase separation, reentrant phase behaviour is observed, with the system passing from a monomeric vapour phase to a region of liquid-vapour phase coexistence and then to a vapour phase of clusters as the temperature is decreased at constant density. Here, we present a classical statistical mechanical approach to the determination of the complete phase diagram of such a system. We model the system as a van der Waals fluid, but one where the monomers can assemble into monodisperse clusters that have no attractive interactions with any of the other species. The resulting phase diagrams show a clear region of reentrance. However, for the most physically reasonable parameter values of the model, this behaviour is restricted to a certain range of density, with phase separation still persisting at high densities.

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Aleks Reinhardt, Alexander J. Williamson, Jonathan P. K. Doye, Jesús Carrete, Luis M. Varela, Ard A. Louis. 2010-10-22. Reentrant phase behaviour for systems with competition between phase separation and self-assembly. https://doi.org/10.1063/1.3557059

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