Self-assembly of three-dimensional ensembles of magnetic particles with laterally shifted dipoles

Arzu B. Yener; Sabine H. L. Klapp

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arXiv · 1510.00196

Self-assembly of three-dimensional ensembles of magnetic particles with laterally shifted dipoles

Arzu B. Yener·Sabine H. L. Klapp

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Abstract

We consider a model of colloidal spherical particles carrying a permanent dipole moment which is laterally shifted out of the particles' geometrical centres, i.e. the dipole vector is oriented perpendicular to the radius vector of the particles. Varying the shift $δ$ from the centre, we analyze ground state structures for two, three and four hard spheres, using a simulated annealing procedure. We also compare to earlier ground state results. We then consider a bulk system at finite temperatures and different densities. Using Molecular Dynamics simulations, we examine the equilibrium self-assembly properties for several shifts. Our results show that the shift of the dipole moment has a crucial impact on both, the ground state configurations as well as the self-assembled structures at finite temperatures.

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Arzu B. Yener, Sabine H. L. Klapp. 2015-11-03. Self-assembly of three-dimensional ensembles of magnetic particles with laterally shifted dipoles. https://arxiv.org/abs/1510.00196

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