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Grain Boundary Scars and Spherical Crystallography

A. R. Bausch·M. J. Bowick·A. Cacciuto·A. D. Dinsmore·M. F. Hsu·D. R. Nelson·M. G. Nikolaides·A. Travesset·D. A. Weitz
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Abstract

We describe experimental investigations of the structure of two-dimensional spherical crystals. The crystals, formed by beads self-assembled on water droplets in oil, serve as model systems for exploring very general theories about the minimum energy configurations of particles with arbitrary repulsive interactions on curved surfaces. Above a critical system size we find that crystals develop distinctive high-angle grain boundaries, or scars, not found in planar crystals. The number of excess defects in a scar is shown to grow linearly with the dimensionless system size. The observed slope is expected to be universal, independent of the microscopic potential.

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A. R. Bausch, M. J. Bowick, A. Cacciuto, A. D. Dinsmore, M. F. Hsu, D. R. Nelson, M. G. Nikolaides, A. Travesset, D. A. Weitz. 2003-03-15. Grain Boundary Scars and Spherical Crystallography. https://doi.org/10.1126/science.1081160

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