Debye type dielectric relaxation in carbon nano-balls' and 4-DMAABCA acid doped E7 coded nematic liquid crystal

Senturk E., Okutan M., San S. E., Koysal O.

Journal of Non-Crystalline Solids, vol.354, no.30, pp.3525-3528, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Review
  • Volume: 354 Issue: 30
  • Publication Date: 2008
  • Doi Number: 10.1016/j.jnoncrysol.2008.03.044
  • Journal Name: Journal of Non-Crystalline Solids
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.3525-3528
  • Keywords: Dielectric properties, relaxation, electric modulus, Liquid crystals and molecular liquids
  • Yıldız Technical University Affiliated: No

Abstract

The electrical properties of carbon nano-balls' and 4-dimethylaminoazobenzene-2′-carboxylic acid doped dispersed nematic liquid crystal composite were investigated by impedance spectroscopy technique. The conductivity and capacitance were measured in the frequency range 100 kHz-1 MHz and temperature range 300-380 K. The loss peak was observed in the dielectric loss spectra and was identified as nearly-Debye type relaxation. Cole-Cole plots have been used to describe the characteristic changes of electrical properties in mentioned temperature interval. The sample presents monodispersive relaxation behavior with a relaxation time of ∼10-7 s. The relaxation process is attributed to the dipolar rotation of the long molecular axis and the activation energy is found to be 0.097 eV. © 2008 Elsevier B.V. All rights reserved.