Department of Physics Papers

Document Type

Journal Article

Date of this Version

4-16-2010

Comments

Suggested Citation:
Wang, Z., A.M. Alsayed, A.G. Yodh and Y. Han. (2010). "Two-dimensional freezing criteria for crystallizing colloidal monolayers." The Journal of Chemical Physics. 132, 154501.

© 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.

The following article appeared in The Journal of Chemical Physics and may be found at http://dx.doi.org/10.1063/1.3372618.

Abstract

Video microscopy was employed to explore crystallization of colloidal monolayers composed of diameter-tunable microgel spheres. Two-dimensional (2D) colloidal liquids were frozen homogenously into polycrystalline solids, and four 2D criteria for freezing were experimentally tested in thermal systems for the first time: the Hansen–Verlet freezing rule, the Löwen–Palberg– Simon dynamical freezing criterion, and two other rules based, respectively, on the split shoulder of the radial distribution function and on the distribution of the shape factor of Voronoi polygons. Importantly, these freezing criteria, usually applied in the context of single crystals, were demonstrated to apply to the formation of polycrystalline solids. At the freezing point, we also observed a peak in the fluctuations of the orientational order parameter and a percolation transition associated with caged particles. Speculation about these percolated clusters of caged particles casts light on solidification mechanisms and dynamic heterogeneity in freezing.

 

Date Posted: 08 November 2010

This document has been peer reviewed.