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arXiv · 0805.1181

Percolative properties of hard oblate ellipsoids of revolution with a soft shell

Gianluca Ambrosetti·Niklaus Johner·Claudio Grimaldi·Andrea Danani·Peter Ryser
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Abstract

We present an in-depth analysis of the geometrical percolation behavior in the continuum of random assemblies of hard oblate ellipsoids of revolution. Simulations where carried out by considering a broad range of aspect-ratios, from spheres up to aspect-ratio 100 plate-like objects, and with various limiting two particle interaction distances, from 0.05 times the major axis up to 4.0 times the major axis. We confirm the widely reported trend of a consistent lowering of the hard particle critical volume fraction with the increase of the aspect-ratio. Moreover, assimilating the limiting interaction distance to a shell of constant thickness surrounding the ellipsoids, we propose a simple relation based on the total excluded volume of these objects which allows to estimate the critical concentration from a quantity which is quasi-invariant over a large spectrum of limiting interaction distances. Excluded volume and volume quantities are derived explicitly.

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Gianluca Ambrosetti, Niklaus Johner, Claudio Grimaldi, Andrea Danani, Peter Ryser. 2008-05-10. Percolative properties of hard oblate ellipsoids of revolution with a soft shell. https://doi.org/10.1103/physreve.78.061126

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