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arXiv · 2108.09286

Inherent Structure Landscape of Hard Spheres Confined to Narrow Cylindrical Channels

Mahdi Zarif·Raymond J. Spiteri·Richard K. Bowles
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Abstract

The inherent structure landscape for a system of hard spheres confined to a hard cylindrical channel, such that spheres can only contact their first and second neighbours, is studied using an analytical model that extends previous results [Phys. Rev. Lett. 115, 025702 (2015)] to provide a comprehensive picture of jammed packings over a range of packing densities. In the model, a packing is described as an arrangement of $k$ helical sections, separated by defects, that have alternating helical twist directions and where all spheres satisfy local jamming constraints. The structure of each helical section is determined by a single helical twist angle, and a jammed packing is obtained by minimizing the length of the channel per particle with respect to the $k$ helical section angles. An analysis of a small system of $N=20$ spheres shows that the basins on the inherent structure landscape associated with these helical arrangements split into a number of distinct jammed states separated by low barriers giving rise to a degree of hierarchical organization. The model accurately predicts the geometric properties of packings generated using the Lubachevsky and Stillinger compression scheme ($N=10^4$) and provides insight into the nature of the probability distribution of helical section lengths.

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Mahdi Zarif, Raymond J. Spiteri, Richard K. Bowles. 2021-08-20. Inherent Structure Landscape of Hard Spheres Confined to Narrow Cylindrical Channels. https://doi.org/10.1103/physreve.104.064602

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