Negative Poisson's ratio materials via isotropic interactions.
نویسندگان
چکیده
We show that under tension a classical many-body system with only isotropic pair interactions in a crystalline state can, counterintuitively, 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, a negative Poisson's ratio can be exhibited even when the material is constrained to be elastically isotropic.
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عنوان ژورنال:
- Physical review letters
دوره 101 8 شماره
صفحات -
تاریخ انتشار 2008