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Alignment of nematic liquid crystals on mixed Langmuir-Blodgett mono-layers

V. S. U. Fazio·L. Komitov·S. T. Lagerwall
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Abstract

Mono-layers of stearic and behenic acids and mixtures of them in different proportions, deposited with the Langmuir-Blodgett technique, were used to study the alignment and the alignment dynamics in nematic liquid crystal cells. A relaxation process from a splay-bend flow induced metastable orientation to the homeotropic one occurs. The lifetime of the metastable state was found to depend on the mono-layer composition. The transition between the homeotropic and the conical anchoring was found to be irreversible in the case of the mixed aligning mono-layers: on cooling from the isotropic phase a quasi-planar nematic state (schlieren texture) appears. It is stable in a range of a few degrees below the clearing point and, on decreasing the temperature, relaxes to the homeotropic state in form of expanding domains.

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V. S. U. Fazio, L. Komitov, S. T. Lagerwall. 1997-09-16. Alignment of nematic liquid crystals on mixed Langmuir-Blodgett mono-layers. https://doi.org/10.1016/s0040-6090(98)00740-8

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