| In this work we investigate some aspects of the physics of associating fluids composed of patchy colloids - spherical particles which interact through a combination of centrally symmetrical repulsion and short-ranged directional attractive forces, arising from the presence of 'sticky spots' on the spheres' surfaces. Such systems were found to display very interesting phase behaviour, including re-entrant and pinched liquid/vapour coexistence curves, in the case when the spots decorating each colloid are not identical. We turn our attention to associating fluids placed in much less extensively studied inhomogeneous setups. Our model particles are hard spheres enhanced with three sticky spots each, out of which two are of type A and one of type B. Consequently, the colloids may form three types of bonds: AA (which lead to formation of linear chains), AB (producing Y-junctions), and BB (giving rise to X-junctions). We carry out a microscopic density functional theory (DFT) investigation of the properties of the liquid/vapour interface of the model fluid, and compare the results with an earlier analysis, which applied a Landau-type theory. |
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