African Journal of Physics Vol. 2 (2), 7 pages, February, 2014. © International Scholars Journals
Full Length Research Paper
Thermodynamical, dielectric and optical properties of liquid crystal sample signalling SmA point
Nandamuri Taraka,1 Rama Rao 1, Rama Raju, Alluri Sita,1 Pingali Venkayya 2
1Department of Physics, Lucknow University, Lucknow-226006, India
2Applied Chemistry Department,Faculty of Technology and Engineering,The Maharaja Sayajirao University of
Baroda,P.B.No. 51, Kalabhavan, Vadodara-390 001, India.
Accepted 20 November, 2013
Abstract
The dielectric constant and dielectric loss with dielectric anisotropy have been measured as a function of temperature in the frequency range of 1 kHz to 10 MHz for a newly synthesized liquid crystal sample-exhibiting SmA phase. The measurement in SmA phase indicates dielectric relaxation at frequency 4.778 kHz for 80 0C. The Enthalpy of activation was found to be 14.57 Kcal/mole. The results have been explained on the basis of Maier and Meier theory. The optical anisotropy study, white light transmit-tance study has also been carried out on the sample. Phase transition temperature matches very well as obtained from all the above mentioned measurement techniques. Optical anisotropy data has been used to determine order parameter by Vuks approach and its variation with temperature has been discussed.
Key words: Liquid Crystals, Dielectric Properties, Refractive Indices, Optical Transmittance.