Calculation of the Dielectric Constant of a Ferroelectric Liquid Crystal From a Mean Field Model

Date

2011-01-01

Author

YURTSEVEN, HASAN HAMİT
Yurtseven, Hasan Hamit

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

78
views

0
downloads

The static dielectric constant epsilon(perpendicular to) of the ferroelectric liquid crystal 4-(3-methyl-2-chlorobutanoyloxy)-4'--heptyloxybiphenyl (A7) with high spontaneous polarization is calculated as a function of temperature using a mean field model. This calculation is performed close to the smectic A-isotropic liquid (SmA-I) transition for pure optically active compound (T-c = 81.6 degrees C). For this calculation of epsilon(perpendicular to), the free energy of the SmA phase is expanded in terms of the orientational order parameter. and spontaneous polarization P with P-2 psi(2).

Subject Keywords

Dielectric constant, Ferroelectric liquid crystal, A7

URI

https://hdl.handle.net/11511/49229

Journal

FERROELECTRICS

DOI

https://doi.org/10.1080/00150193.2011.594007

Collections

Department of Physics, Article

Suggestions

OpenMETU
Core

A First-Order Transition of the Smectic A-Smectic C* in Ferroelectric Liquid Crystals Kilit, E.; Yurtseven, Hasan Hamit (2012-01-01) The static dielectric constant is calculated as a function of temperature using a mean field model close to the smectic A-smectic C* transition for the ferroelectric liquid crystal 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl (A7). This calculation of the dielectric constant is performed for the pure optically active compound (T-c = 73.4 degrees C) and the temperature range is determined for a first-order smectic A-smectic C* transition from the mean field model. Our predicted values describe adequ...
Critical behaviour of the dielectric constant for the smectic AC* transition under the electric field in ferroelectric liquid crystals Yurtseven, Hasan Hamit (2012-01-01) The temperature dependencies of the dielectric constant and the tilt angle (order parameter) are calculated under the electric field for the smectic A-smectic C* (AC*) transition in 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl (A7). The dielectric constant is fitted to the experimental data by using our mean field model with the biquadratic coupling between the spontaneous polarisation P and the tilt angle theta. Our results show that the mean field model with the P-2 theta(2) coupling describes sa...
Critical behavior of the spontaneous polarization and the dielectric susceptibility close to the cubic-tetragonal transition in BaTiO3 Yurtseven, Hasan Hamit (2015-09-01) Using Landau mean field model, the spontaneous polarization and the dielectric susceptibility are analyzed as functions of temperature and pressure close to the cubic-tetragonal (ferroelectric-paraelectric) transition in BaTiO3. From the analysis of the dielectric susceptibility and the spontaneous polarization, the critical exponents are deduced in the classical and quantum limits for BaTiO3. From the critical behavior of the dielectric susceptibility, the spontaneous polarization can be described for the ...
Application of the spectroscopic modifications of Pippard relations to NaNO2 in the ferroelectric phase Yurtseven, Hasan Hamit (2001-01-01) This study examines a linear variation of the specific heat C-P with the frequency shifts 1/nu(partial derivative nu/partial derivativeT) for the Brillouin frequencies of the L-mode [010], [001] and [100] in the ferroelectric phase of NaNO2 according to our spectroscopically modified Pippard relation. We obtain this linear relationship for those modes studied and calculate dT(C)/dP in the ferroelectric phase of NaNO2. Our calculated values of dT(C)/dP for the [001] and [100] modes are in good agreement with...
Calculation of the damping constant and the order parameter for the lattice mode in ferroelectric PbTiO3 Kiraci, A.; Yurtseven, Hasan Hamit (2013-07-25) The temperature dependences of the damping constant and the order parameter are calculated for the lattice mode of E (1TO) in PbTiO3 using the experimental data by the pseudospin- phonon coupled model and the enrgy fluctuation model. Calculation of the damping constant of soft mode is performed in the temperature range of 400- 490 degrees C close to the ferroelectric- paraelectric transition (T-C= 493 degrees C) in PbTiO3. By relating the frequency to the order parameter, the temperature dependence of the R...

Citation Formats

H. H. YURTSEVEN and H. H. Yurtseven, “Calculation of the Dielectric Constant of a Ferroelectric Liquid Crystal From a Mean Field Model,” FERROELECTRICS, pp. 56–61, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/49229.