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arXiv · 0910.1681

Phase diagram and structural properties of a simple model for one-patch particles

Achille Giacometti·Fred Lado·Julio Largo·Giorgio Pastore·Francesco Sciortino
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Abstract

We study the thermodynamic and structural properties of a simple, one-patch fluid model using the reference hypernetted-chain (RHNC) integral equation and specialized Monte Carlo simulations. In this model, the interacting particles are hard spheres, each of which carries a single identical, arbitrarily-oriented, attractive circular patch on its surface; two spheres attract via a simple square-well potential only if the two patches on the spheres face each other within a specific angular range dictated by the size of the patch. For a ratio of attractive to repulsive surface of 0.8, we construct the RHNC fluid-fluid separation curve and compare with that obtained by Gibbs ensemble and grand canonical Monte Carlo simulations. We find that RHNC provides a quick and highly reliable estimate for the position of the fluid-fluid critical line. In addition, it gives a detailed (though approximate) description of all structural properties and their dependence on patch size.

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Achille Giacometti, Fred Lado, Julio Largo, Giorgio Pastore, Francesco Sciortino. 2009-10-09. Phase diagram and structural properties of a simple model for one-patch particles. https://doi.org/10.1063/1.3256002

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