Investigating of dielectric anisotropy and birefringence of binary liquid crystal mixtures

Year 2017, Volume: 1 Issue: 1, 1 - 6, 12.10.2017

Şükrü Özğan

https://doi.org/10.32571/ijct.335298

Cited By: 1

Abstract

Absorbance,
capacitance, conductance, dielectric anisotropy and birefringence properties
and splay elastic coefficient of 4’-Hexyl-4-biphenylcarbonitrile (6CB) and its
mixture with 4’-Octyl-4-biphenylcarbonitrile (8CB) were investigated. The
absorbance was studied using the UV-visible spectrophotometry.
Capacitance, conduction and dielectric
measurements for 6CB and its mixture were performed in  0-1000
kHz frequency range at the room temperature. Capacitance-voltage and capacitance-frequency
changes were investigated for the mixture. Threshold voltage was determined as 2.1 V. It was
seen that the capacitance suddenly damped at this voltage. Capacitance is large at lower frequencies
and small at higher frequencies than 100 kHz. The conductance-voltage change was obtained for the mixture. The conduction suddenly rose at the threshold voltage. The conduction is small at lower frequencies and large at higher
frequencies. Dielectric, birefringence index and splay elastic constant were investigated
for 6CB/8CB mixture. The measured values of the mixture are bigger than 6CB
values up to the certain frequency.

Keywords

Electric properties, Elasticity, Optical properties, Liquid crystals

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