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Updated: May 22, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Order parameters , , and of aligned nematic liquid-crystalline polymer as determined by numerical simulation of
T S Yankova1, A Yu Bobrovsky, A Kh Vorobiev
1Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Leninskiye gory, 1/3, Russia. ya.tatiana@gmail.com
Abstract:
High rank order parameters may comprise substantial information about molecular orientational distribution of liquid-crystalline materials. There are few experimental procedures targeted at the determination of high rank order parameters. We suggest a procedure for the determination of order parameters of a spin probe by numerical simulation of electron paramagnetic resonance (EPR) spectra. The procedure is based on revealing the molecular orientation axis of a spin probe. Order parameters
,
, and
of the spin probe in aligned liquid-crystalline polymer have been measured by the suggested procedure. It was shown that the procedure gives more reliable and complete characteristics of molecular order than does polarized UV-visible spectroscopy.
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