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arXiv · 1309.5225

Self-assembly in chains, rings and branches: a single component system with two critical points

Lorenzo Rovigatti·José Maria Tavares·Francesco Sciortino
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Abstract

We study the interplay between phase separation and self-assembly in chains, rings and branched structures in a model of particles with dissimilar patches. We extend Wertheim's first order perturbation theory to include the effects of ring formation and theoretically investigate the thermodynamics of the model. We find a peculiar shape for the vapor-liquid coexistence, featuring re-entrant behavior in both phases and two critical points, despite the single-component nature of the system. The emergence of the lower critical point is caused by the self-assembly of rings taking place in the vapor, generating a phase with lower energy and lower entropy than the liquid. Monte Carlo simulations of the same model fully support these unconventional theoretical predictions.

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Lorenzo Rovigatti, José Maria Tavares, Francesco Sciortino. 2013-09-20. Self-assembly in chains, rings and branches: a single component system with two critical points. https://doi.org/10.1103/physrevlett.111.168302

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