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Updated: Mar 7, 2026
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Molecular Structure of Canonical Liquid Crystal Interfaces
Monirosadat Sadati1, Hadi Ramezani-Dakhel, Wei Bu
1Argonne National Laboratory , Argonne, Illinois 60439, United States.
Abstract:
Numerous applications of liquid crystals rely on control of molecular orientation at an interface. However, little is known about the precise molecular structure of such interfaces. In this work, synchrotron X-ray reflectivity measurements, accompanied by large-scale atomistic molecular dynamics simulations, are used for the first time to reconstruct the air-liquid crystal interface of a nematic material, namely, 4-pentyl-4'-cyanobiphenyl (5CB). The results are compared to those for 4-octyl-4'-cyanobiphenyl (8CB) which, in addition to adopting isotropic and nematic states, can also form a smectic phase. Our findings indicate that the air interface imprints a highly ordered structure into the material; such a local structure then propagates well into the bulk of the liquid crystal, particularly for nematic and smectic phases.
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