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arXiv · 1506.08632

Pattern formation in binary fluid mixtures induced by short-range competing interactions

C. Bores·E. Lomba·A. Perera·N. G. Almarza
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Abstract

Molecular dynamics simulations and integral equation calculations of a simple equimolar mixture of diatomic molecules and monomers interacting via attractive and repulsive short-range potentials show the existence of pattern formation (microheterogeneity), mostly due to depletion forces away from the demixing region. Effective site-site potentials extracted from the pair correlation functions using an inverse Monte Carlo approach and an integral equation inversion procedure exhibit the features characteristic of a short-range attractive and long-range repulsive potential. When charges are incorporated into the model, this becomes a coarse grained representation of a room temperature ionic liquid, and as expected, intermediate range order becomes more pronounced and stable.

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C. Bores, E. Lomba, A. Perera, N. G. Almarza. 2015-06-29. Pattern formation in binary fluid mixtures induced by short-range competing interactions. https://doi.org/10.1063/1.4928524

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