Interfacial Curvature Impacted Defect Formation in Colloidal Materials
Gabrielle Jones, University of Michigan
From catalysis to cosmetics, innovative new materials are designed to meet the need for cost-effective and high-quality products. To achieve favorable properties colloidal materials and their self assembly can be manipulated using a conceptual framework that allows each design parameter to exist along discrete or continuous gradients, such as roundedness and shape, to create a plethora of crystal structures.1-3 Emulsions stabilized by the addition of colloidal particles at the fluid-fluid interface can be used to encapsulate valuable medication for controlled drug delivery, facilitate interfacial bio-catalysis, or control swelling dynamics to drive particle assembly.4-6 In our work we simulate emulsion systems comprised of shape anisotropic particles confined to the surface of a sphere. Circle packing on the surface of a sphere (and equivalently sphere packing on the sphere) has been extensively studied, showing optimal packings with various symmetries including icosahedral, snub cube, and snub dodecahedral.7 We expand this work by assembling symmetric packings of small numbers of tetrahedra on a sphere surface in a similar fashion. We additionally show novel defect patterns and motifs for large particle number systems for select Platonic and Archimedean solids.
References:
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2P. F. Damasceno, M. Engel, and S. C. Glotzer, “Predictive Self-Assembly of Polyhedra into Complex Structures,” Science, vol. 337, pp. 453–457, July 2012.
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5Z. Sun, U. Glebe, H. Charan, A. Böker, and C. Wu, “Enzyme–Polymer Conjugates as Robust Pickering Interfacial Biocatalysts for Efficient Biotransformations and One-Pot Cascade Reactions,” Angewandte Chemie International Edition, vol. 57, pp. 13810–13814, Oct. 2018.
6L. Tran and K. J. M. Bishop, “Swelling Cholesteric Liquid Crystal Shells to Direct the Assembly of Particles at the Interface,” ACS Nano, vol. 14, pp. 5459–5467, May 2020.
7B. W. Clare and D. L. Kepert, “The optimal packing of circles on a sphere,” Journal of Mathematical Chemistry, vol. 6, pp. 325–349, Dec. 1991.
Abstract Author(s): Gabrielle Jones, Philipp Schoenhoefer, Sharon Glotzer