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arXiv · 2109.00189

Connecting packing efficiency of binary hard sphere systems to their intermediate range structure

Houfei Yuan·Zhen Zhang·Walter Kob·Yujie Wang
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Abstract

Using computed x-ray tomography we determine the three dimensional (3d) structure of binary hard sphere mixtures as a function of composition and size ratio of the particles, q. Using a recently introduced four-point correlation function we reveal that this 3d structure has on intermediate and large length scales a surprisingly regular order, the symmetry of which depends on q. The related structural correlation length has a minimum at the composition at which the packing fraction is highest. At this composition also the number of different local particle arrangements has a maximum, indicating that efficient packing of particles is associated with a structure that is locally maximally disordered.

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Houfei Yuan, Zhen Zhang, Walter Kob, Yujie Wang. 2021-09-01. Connecting packing efficiency of binary hard sphere systems to their intermediate range structure. https://doi.org/10.1103/physrevlett.127.278001

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