Physical Properties of Pure and Nano Agdoped Liquid Crystalline Compounds Containing 1,3,4-Oxadizole Unit

Ammar H. Al-Dujaili; Juman A. Naser; Taki A. Himdan; Issam A. Latif; Yousif I. Mohammed

Ammar H. Al-Dujaili Department of Chemistry, Faculty of Science, University of Jordan, Amman, Jordan.
Juman A. Naser Department of Chemistry, College of Education for pure Sciences, Ibn Al-Hiatham, University of Baghdad, Baghdad, Iraq.
Taki A. Himdan Department of Chemistry, College of Education for pure Sciences, Ibn Al-Hiatham, University of Baghdad, Baghdad, Iraq.
Issam A. Latif
Yousif I. Mohammed Department of Chemistry, College of Education for pure Sciences, Ibn Al-Hiatham, University of Baghdad, Baghdad, Iraq.

Keywords: Liquid Crystals, Dielectric Permittivity, Electrical Conductivity, Relaxation Time, Activation Energy, Doped Liquid Crystals, Silver Nanoparticles.

Abstract

Dielectric properties and other physical properties such as electrical conductivity (AC) and relaxation time or activation energy have been studied for two systems pure LC [V]_6,6, [V]_7,6, [V]_8,6, [V]_6,7, [V]_7,7 and [V]_8,7 and their doped with silver nanoparticles. The results show the increasing in real dielectric permittivity έ with increasing length terminal chain. So the real dielectric permittivity increasing with raising temperature. To compare between the values of at (400) Hz and (4000) Hz we observe these values at the low frequency are larger than that in high frequency. Generally, one can see that the doping of Ag nano particles effectively reduced the permittivity of the LC materials with its large electric dipole moment. The electrical conductivity value for pure LC samples in general increases with increasing temperature. So we observed increasing of electrical conductivity values at high frequency. The time scale is discussed in terms of the Arrhenius plot. Generally, with increasing the temperature the time period that spend by molecules at the transition state will increase. The activation energy Ea values show the increase in the activation energy to the doped systems.

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