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Large effect of polydispersity on defect concentrations in colloidal crystals

Sander Pronk·Daan Frenkel
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Abstract

We compute the equilibrium concentration of stacking faults and point defects in polydisperse hard-sphere crystals. We find that, while the concentration of stacking faults remains similar to that of monodisperse hard sphere crystals, the concentration of vacancies decreases by about a factor two. Most strikingly, the concentration of interstitials in the maximally polydisperse crystal may be some six orders of magnitude larger than in a monodisperse crystal. We show that this dramatic increase in interstitial concentration is due to the increased probability of finding small particles and that the small-particle tail of the particle size distribution is crucial for the interstitial concentration in a colloidal crystal.

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Sander Pronk, Daan Frenkel. 2004-02-03. Large effect of polydispersity on defect concentrations in colloidal crystals. https://doi.org/10.1063/1.1667880

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