CALCULATION OF THE TILT ANGLE AND SUSCEPTIBILITY AS FUNCTION OF TEMPERATURE AND THE ELECTRIC FIELD CLOSE TO THE SM A-SMC TRANSITION IN C7

Date

2017-09-10

Author

Aksoy, Sinan
Kurt, Mustafa
Yurtseven, Hasan Hamit

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Smectic A – Smectic C* transition in the ferroelectric liquid crystal (C7) is studied as a function of the electric field and the temperature. By expanding the free energy in terms of the tilt angle θ (Smectic C* phase) and the polarization P with a linear coupling between θ and P (Pθ) in mean field theory, the tilt angle is calculated as a function of the electric field (θ versus E) at constant temperatures with respect to the transition temperature for C7 using the observed data from the literature. Also, by extracting the tilt angle from the observed electric displacements at various temperatures (at constant field strength) the inverse tilt angle susceptibility (), derived from the free energy, is fitted to the observed data for the dielectric constant and the fitted parameters are determined. Our calculated θ and χθ. show that the mean field theory explains adequately the observed behavior of the Smectic A – Smectic C* transition in the liquid crystals C7.

URI

https://hdl.handle.net/11511/81720
https://cdnsciencepub.com/doi/abs/10.1139/cjp-2017-0731

Conference Name

TURKISH PHYSICAL SOCIETY 33RD INTERNATIONAL PHYSICS CONGRESS, Türkiye, 6 - 10 Eylül 2017

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Department of Physics, Conference / Seminar

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Citation Formats

S. Aksoy, M. Kurt, and H. H. Yurtseven, “CALCULATION OF THE TILT ANGLE AND SUSCEPTIBILITY AS FUNCTION OF TEMPERATURE AND THE ELECTRIC FIELD CLOSE TO THE SM A-SMC TRANSITION IN C7,” presented at the TURKISH PHYSICAL SOCIETY 33RD INTERNATIONAL PHYSICS CONGRESS, Türkiye, 6 - 10 Eylül 2017, 2017, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/81720.