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Effective pair interactions between colloidal particles at a nematic-isotropic interface

D. Andrienko·M. Tasinkevych·S. Dietrich
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Abstract

The Landau-de Gennes free energy is used to study theoretically the interaction of parallel cylindrical colloidal particles trapped at a nematic-isotropic interface. We find that the effective interaction potential is non-monotonic. The corresponding force-distance curves exhibit jumps and hysteresis upon approach/separation due to the creation/annihilation of topological defects. Minimization results suggest a simple empirical pair potential for the effective colloid-colloid interaction at the interface. We propose that the interface-mediated interaction can play an important role in self-organization and clustering of colloidal particles at such interfaces.

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D. Andrienko, M. Tasinkevych, S. Dietrich. 2005-01-24. Effective pair interactions between colloidal particles at a nematic-isotropic interface. https://doi.org/10.1209/epl%2Fi2004-10455-3

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