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arXiv · 1106.5561

Degenerate Quasicrystal of Hard Triangular Bipyramids

Amir Haji-Akbari·Michael Engel·Sharon C Glotzer
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Abstract

We report a degenerate quasicrystal in Monte Carlo simulations of hard triangular bipyramids each composed of two regular tetrahedra sharing a single face. The dodecagonal quasicrystal is similar to that recently reported for hard tetrahedra [Haji-Akbari et al., Nature (London) 462, 773 (2009)] but degenerate in the pairing of tetrahedra, and self-assembles at packing fractions above 54%. This notion of degeneracy differs from the degeneracy of a quasiperiodic random tiling arising through phason flips. Free energy calculations show that a triclinic crystal is preferred at high packing fractions.

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Amir Haji-Akbari, Michael Engel, Sharon C Glotzer. 2011-11-22. Degenerate Quasicrystal of Hard Triangular Bipyramids. https://doi.org/10.1103/physrevlett.107.215702

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