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arXiv · 1501.01795

Low-density crystals in charged colloids : Comparison with Yukawa theory

Ioatzin Ríos de Anda·Antonia Statt·Francesco Turci·C. Patrick Royall
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Abstract

Charged colloids can behave as Yukawa systems, with similar phase behaviour. Using particle- resolved studies, we consider a system with an unusually long Debye screening length which forms crystals at low colloid volume fraction ϕ ~ 0.01. We quantitatively compare this system with the Yukawa model and find that its freezing point is compatible with the theoretical prediction but that the crystal polymorph is not always that expected. In particular we find body-centred cubic crystals where face-centred cubic crystals are expected.

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Ioatzin Ríos de Anda, Antonia Statt, Francesco Turci, C. Patrick Royall. 2015-01-08. Low-density crystals in charged colloids : Comparison with Yukawa theory. https://doi.org/10.1002/ctpp.201400099

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