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arXiv · 0709.4399

Stability of the decagonal quasicrystal in the Lennard-Jones-Gauss system

Michael Engel·Hans-Rainer Trebin
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Abstract

Although quasicrystals have been studied for 25 years, there are many open questions concerning their stability: What is the role of phason fluctuations? Do quasicrystals transform into periodic crystals at low temperature? If yes, by what mechanisms? We address these questions here for a simple two-dimensional model system, a monatomic decagonal quasicrystal, which is stabilized by the Lennard-Jones-Gauss potential in thermodynamic equilibrium. It is known to transform to the approximant Xi, when cooled below a critical temperature. We show that the decagonal phase is an entropically stabilized random tiling. By determining the average particle energy for a series of approximants, it is found that the approximant Xi is the one with lowest potential energy.

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Michael Engel, Hans-Rainer Trebin. 2008-06-30. Stability of the decagonal quasicrystal in the Lennard-Jones-Gauss system. https://doi.org/10.1080/14786430802132548

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