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Vacancy-stabilized crystalline order in hard cubes.

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 approximately 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.

SUBMITTER: Smallenburg F

PROVIDER: S-EPMC3497827 | biostudies-other | 2012 Oct

REPOSITORIES: biostudies-other

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Vacancy-stabilized crystalline order in hard cubes.

Smallenburg Frank F Filion Laura L Marechal Matthieu M Dijkstra Marjolein M

Proceedings of the National Academy of Sciences of the United States of America 20120910 44

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 approximately 6.4% near bulk coexistence. Remarkably, we find that vacancies increase the positional order in the system. Finally, we ...[more]

PMID: 23012241

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