Shear of Molecularly Confined Liquid Crystals. 1. Orientation and

traced from observation through the eyepiece, for different orientations of the 6CB confined between mica surfaces crystallographically parallel to ea...
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4466

Langmuir 1997, 13, 4466-4473

Shear of Molecularly Confined Liquid Crystals. 1. Orientation and Transitions under Confinement Joanna Janik,† Rafael Tadmor, and Jacob Klein* Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel Received May 7, 1996. In Final Form: May 20, 1997X Using a surface force balance, we have examined the orientation of a nematic liquid crystal (6CB) confined between mica surfaces. By simultaneous measuring of the force and the refractive index profile, we were able to distinguish between planar, planar twisted, and homeotropic orientation of the nematic. When the mica was exposed to air for short periods (