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arXiv · 2102.11424

Asymmetric Assembly of Lennard-Jones Janus Dimers

Sina Safaei·Caleb Todd·Jack Yarndley·Shaun Hendy·Geoff R. Willmott
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Abstract

Self-assembly of Janus (or `patchy') particles is dependent on the precise interaction between neighbouring particles. Here, the orientations of two amphiphilic Janus spheres within a dimer in an explicit fluid are studied with high geometric resolution. Molecular dynamics simulations and first-principles energy calculations are used with hard- and soft-sphere Lennard-Jones potentials, and temperature and hydrophobicity are varied. The most probable centre-centre-pole angles are in the range 40{\deg} to 55{\deg}, with pole-to-pole alignment not observed due to orientational entropy. Angles near 90{\deg} are energetically unfavoured due to solvent exclusion, and we unexpectedly found that the relative azimuthal angle between the spheres is affected by solvent ordering.

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Sina Safaei, Caleb Todd, Jack Yarndley, Shaun Hendy, Geoff R. Willmott. 2021-02-23. Asymmetric Assembly of Lennard-Jones Janus Dimers. https://doi.org/10.1103/physreve.104.024602

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