Calculation of Dipolar Flexoelectric Coefficients in Liquid Crystal with Hard Pear Shape Molecules

Document Type : Full length research Paper

Authors

1 Dep. of Physics, Yasouj University

2 Dep. of Physics, Yasouj Universty

3 Associated Professor/ Yasouj University

Abstract

In liquid crystals, pear-shaped and banana molecules find a splay and bend arrangements, due to their asymmetry. In these crystals, the director deviation from equilibrium produces pure polarization. This effect is called Flexoelectricity. Flexoelectric coefficients in liquid crystals were derived from simulation and experimental methods. In density functional theory, these coefficients depend on the direct correlation and the angular distribution functions of molecules. In this work, by using parameterized hard Gaussian overlap method the closest distance of hard pear shape molecules is calculated. By using this closest distance, the approximate direct correlation function of pear-shaped molecules is obtained. Using this correlation function and deduced proper distribution function, the dipolar Flexoelectric coefficients for liquid crystals with elongations 3 and 5 pear-shaped molecules are calculated. The results are consistent with the simulation results qualitatively.

Keywords

References

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Journal of Research on Many-body Systems
Volume 9, Issue 1
فصل بهار
May 2019
Pages 115-123

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History

  • Receive Date: 04 October 2017
  • Revise Date: 20 October 2018
  • Accept Date: 28 November 2018

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