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arXiv · 1111.3466

Vacancy-stabilized crystalline order in hard cubes

Frank Smallenburg·Laura Filion·Matthieu Marechal·Marjolein Dijkstra
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Abstract

We examine the effect of vacancies on the phase behavior and structure of systems consisting of hard cubes using event-driven molecular dynamics and Monte Carlo simulations. We find a first-order phase transition between a fluid and a simple cubic crystal phase that is stabilized by a surprisingly large number of vacancies, reaching a net vacancy concentration of ~6.4% near bulk coexistence. Remarkably, we find that vacancies increase the positional order in the system. Finally, we show that the vacancies are delocalized and therefore hard to detect.

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Frank Smallenburg, Laura Filion, Matthieu Marechal, Marjolein Dijkstra. 2011-11-15. Vacancy-stabilized crystalline order in hard cubes. https://doi.org/10.1073/pnas.1211784109

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