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arXiv · 0807.3562

Negative Poisson's ratio materials via isotropic interactions

Mikael C. Rechtsman·Frank H. Stillinger·Salvatore Torquato
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Abstract

We show that under tension, a classical many-body system with only isotropic pair interactions in a crystalline state can, counterintutively, have a negative Poisson's ratio, or auxetic behavior. We derive the conditions under which the triangular lattice in two dimensions and lattices with cubic symmetry in three dimensions exhibit a negative Poisson's ratio. In the former case, the simple Lennard-Jones potential can give rise to auxetic behavior. In the latter case, negative Poisson's ratio can be exhibited even when the material is constrained to be elastically isotropic.

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Mikael C. Rechtsman, Frank H. Stillinger, Salvatore Torquato. 2008-07-22. Negative Poisson's ratio materials via isotropic interactions. https://doi.org/10.1103/physrevlett.101.085501

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