LAUSR

Abstract A comparable study of the dielectric response of PentylCyano Biphenyl (PCB) nematic liquid crystals over the temperature range 297–316°K is reported for two frequencies i.e. 9.0 GHz and 20.9 GHz. The loaded resonant microwave cavity operated in TM010 mode at two different frequencies mentioned above. The theory of perturbation is used to analyze the data. The computation of Activation energy and Relaxation time was done. Calculation for the thermo-dynamical parameters such as ΔG, ΔH and ΔS was done for a suitable temperature range. It has been observed that the change in temperature and the change in frequency both effects the properties such as relaxation time, activation energy, entropy and enthalpy. This method is well known in scientific community for its requirement of small quantity of sample and inherent accuracy. The possible applications are reversible optical memories, beam steering antenna, and fabricating frequency agile components.