Theoretical and numerical investigations of inverse patchy colloids in the fluid phase

Yurij V. Kalyuzhnyi; Emanuela Bianchi; Silvano Ferrari; Gerhard Kahl

doi:10.1063/1.4914345

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arXiv · 1412.4492

Theoretical and numerical investigations of inverse patchy colloids in the fluid phase

Yurij V. Kalyuzhnyi·Emanuela Bianchi·Silvano Ferrari·Gerhard Kahl

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Abstract

We investigate the structural and thermodynamic properties of a new class of patchy colloids, referred to as inverse patchy colloids (IPCs) in their fluid phase via both theoretical methods and simulations. IPCs are nano- or micro- meter sized particles with differently charged surface regions. We extend conventional integral equation schemes to this particular class of systems: our approach is based on the so-called multi-density Ornstein-Zernike equation, supplemented by the associative Percus-Yevick approximation (APY). To validate the accuracy of our framework, we compare the obtained results with data extracted from $NpT$ and $NVT$ Monte Carlo simulations. In addition, other theoretical approaches are used to calculate the properties of the system: the reference hypernetted-chain (RHNC) method and the Barker-Henderson thermodynamic perturbation theory. Both APY and RHNC frameworks provide accurate predictions for the pair distribution functions: APY results are in slightly better agreement with MC data, in particular at lower temperatures where the RHNC solution does not converge.

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Yurij V. Kalyuzhnyi, Emanuela Bianchi, Silvano Ferrari, Gerhard Kahl. 2014-12-15. Theoretical and numerical investigations of inverse patchy colloids in the fluid phase. https://doi.org/10.1063/1.4914345

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