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Title: Directed assembly of small binary clusters of magnetizable ellipsoids
We report the effect of shape anisotropy and material properties on the directed assembly of binary suspensions composed of magnetizable ellipsoids. In a Monte Carlo simulation, we implement the ellipsoid-dipole model to calculate the pairwise dipolar interaction energy as a function of position and orientation. The analysis explores dilute suspensions of paramagnetic and diamagnetic ellipsoids with different aspect ratios in a superparamagnetic medium. We analyze the local order of binary structuresas a function of particle aspect ratio, medium permeability, and dipolar interaction strength. Our results show that local order and symmetry are tunable under the influence of a uniform magnetic field when one component of the structure is dilute with respect to the other. The simulation results match previously reported experiments on the directed assembly of binary suspension of spheres. Additionally, we report the conditions on particle aspect ratios and medium properties for various structures with rotational symmetries, as well as open and enclosed structures under the influence of a uniform magnetic field.  more » « less
Award ID(s):
2338064
PAR ID:
10566454
Author(s) / Creator(s):
;
Publisher / Repository:
Soft Matter
Date Published:
Journal Name:
Soft Matter
Volume:
20
Issue:
32
ISSN:
1744-683X
Page Range / eLocation ID:
6411 to 6423
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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