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Bulletin of State University of Education. Series: Physics and Mathematics

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DIELECTRIC PROPERTIES OF LIQUID CRYSTAL LC-1289

https://doi.org/10.18384/2310-7251-2020-1-102-110

Abstract

Purpose. We examine experimentally the permittivity in the microwave range and approximate numerically the frequency dependences of the permittivity of a nematic liquid crystal. Methodology and Approach. At a frequency of 39 GHz, measurements of the permittivity and dielectric loss are performed using the waveguide method, and at frequencies up to 10MHz, using the capacitive method. Results. Experimental values of the permittivity of a nematic liquid crystal LC-1289 at a frequency of 39 GHz are obtained. Numerical approximation of dielectric spectra is performed. The dipole relaxation times associated with the rotation of molecules around the short and long axes and the corresponding activation energies are calculated. Theoretical and Practical Implications. The values of the permittivity and dielectric loss are obtained for evaluating the performance characteristics of the working bodies of information display devices.

About the Author

V. A. Emelyanov
Moscow Region State University
Russian Federation


References

1. Емельянов В. А., Шубин А. В. Методика измерения диэлектрической проницаемости нематических жидких кристаллов в СВЧ-диапазоне // Вестник Московского государственного областного университета (Электронный журнал). 2012. № 3. С. 116-119. URL: https://evestnik-mgou.ru/ru/Articles/View/206 (дата обращения:19.12.2019).

2. Брандт А. А. Исследование диэлектриков на сверхвысоких частотах. М.: Государственное издательство физико-математической литературы, 1963. 404 c.

3. Электрически контролируемые анизотропные жидкокристаллические волноводы / Гончаренко И. А., Кабанова О. С., Мельникова Е. А., Романов О. Г., Рушнова И. И., Толстик А. Л. // Журнал Белорусского государственного университета. Физика. 2017. № 2. С. 4-9.

4. Maier W., Meier G. Eine einfache Theorie der dielektrischen Eigenschaften homogen orientierter kristallinglьssiger Phasen des nematischen Typs // Zeitschrift fьr Naturforschung A. 1961. Vol. 16. Iss. 3. P. 262-267.

5. Де Жё В. Физические свойства жидкокристаллических веществ. М.: Мир, 1982. 153 c.

6. Barsoukov E., Macdonald J. R. Impedance spectroscopy: Theory, Experiment, and Applications. Hoboken: Wiley Publ., 2018. 528 p.

7. Raju G. G. Dielectrics in electric fields: Tables, Atoms, and Molecules; second edition. Boca Raton: CRC Press Publ., 2016. 751 p.

8. Cole K. S.; Cole R. H. Dispersion and Absorption in Dielectrics - I Alternating Current Characteristics // The Journal of Chemical Physics. 1941. Vol. 9. Iss. 4. P. 341-352.

9. Cole K. S.; Cole R. H. Dispersion and Absorption in Dielectrics - II Direct Current Characteristics // The Journal of Chemical Physics. 1942. Vol. 10. Iss. 2. P. 98-105.

10. Bergmann K., Roberti D. M., Smyth C. P. Microwave absorption and molecular structure in liquids. XXXI. Analysis in terms of two relaxation times for some aromatic ethers // The Journal of Chemical Physics. 1960. Vol. 64. Iss. 5. P. 665-667.


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