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Updated: Jun 13, 2026

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Morphology of open films of discotic hexagonal columnar liquid crystals as probed by grazing incidence X-ray
Eric Grelet1, Sébastien Dardel, Harald Bock
1Centre de Recherche Paul-Pascal, CNRS -Université de Bordeaux, 115 Avenue Schweitzer, 33600, Pessac, France. grelet@crpp-bordeaux.cnrs.fr
Abstract:
The structure and the orientation of thermotropic hexagonal columnar liquid crystals are studied by grazing incidence X-ray diffraction (GIXD) for different discotic compounds in the geometry of open supported thin films. Whatever the film deposition mode (either spin-coating or vacuum evaporation) and the film thickness, a degenerate planar alignment with the liquid crystalline columns parallel to the substrate is found. However, if a specific thermal process is applied to the liquid crystal film, homeotropic anchoring (columns normal to the interface) can be stabilized in a metastable state.
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