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arXiv · 1007.5402

A numerical study of one-patch colloidal particles: from square-well to Janus

Francesco Sciortino·Achille Giacometti·Giorgio Pastore
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Abstract

We perform numerical simulations of a simple model of one-patch colloidal particles to investigate: (i) the behavior of the gas-liquid phase diagram on moving from a spherical attractive potential to a Janus potential and (ii) the collective structure of a system of Janus particles. We show that, for the case where one of the two hemispheres is attractive and one is repulsive, the system organizes into a dispersion of orientational ordered micelles and vesicles and, at low $T$, the system can be approximated as a fluid of such clusters, interacting essentially via excluded volume. The stability of this cluster phase generates a very peculiar shape of the gas and liquid coexisting densities, with a gas coexistence density which increases on cooling, approaching the liquid coexistence density at very low $T$.

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Francesco Sciortino, Achille Giacometti, Giorgio Pastore. 2010-07-30. A numerical study of one-patch colloidal particles: from square-well to Janus. https://doi.org/10.1039/c0cp00504e

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