ANISOTROPY OF DIELECTRIC PERMITTIVITY IN 1-(4-HEXYLCYCLOHEXYL)-4-ISOTHIOCYANATOBENZENE
https://doi.org/10.18384/2310-7251-2019-1-83-96
Abstract
Dielectric properties of the 6CHBT nematic liquid crystal with a polar -NCS end group are studied. The principal values of the dielectric permittivity are determined using the methods of dielectric spectroscopy by varying the sample temperature, the angle between the director and electric field strength vector, and the frequency of the test signal. We use a modified dielectric spectroscopy method that takes into account the parasitic contributions of the measuring system. The characteristic dielectric relaxation times τ of rotation of 6CHBT molecules around their short axis in both the nematic and isotropic phases and the corresponding activation enthalpies are calculated. The temperature dependence of the orientational order parameter over the entire range of the nematic phase existence is constructed using the obtained data and the Maier-Saupe theory.
About the Authors
A. D. Kurilov
Moscow Region State University; MIREA - Russian Technological University
Russian Federation
Russian Federation
N. I. Volosnikova
Moscow Region State University
Russian Federation
Russian Federation
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