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arXiv · 0807.2669

Elasticity and Viscosity of a Lyotropic Chromonic Nematic Studied with Dynamic Light Scattering

Yu. A. Nastishin·K. Neupane·A. R. Baldwin·O. D. Lavrentovich·S. Sprunt
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Abstract

Using dynamic light scattering, we measure for the first time the temperature-dependent elastic moduli and associated orientational viscosity coefficients of the nematic phase in a self-assembled lyotropic chromonic liquid crystal. The bend K3 and splay K1 moduli are an order of magnitude higher than the twist K2 constant. The ratio K3/K1 shows an anomalous increase with temperature; we attribute this to the shortening of the aggregates as temperature increases. The viscosity coefficients also show a significant anisotropy, as well as a strong temperature dependence; in particular, the bend viscosity is three orders of magnitude smaller than the splay and twist viscosities.

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Yu. A. Nastishin, K. Neupane, A. R. Baldwin, O. D. Lavrentovich, S. Sprunt. 2008-07-16. Elasticity and Viscosity of a Lyotropic Chromonic Nematic Studied with Dynamic Light Scattering. https://arxiv.org/abs/0807.2669

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