A non-isothermal activated kinetics of K-SmA transition of the aligned octylcyanobiphenyl

Sharma, D.
July 2012
Journal of Thermal Analysis & Calorimetry;Jul2012, Vol. 109 Issue 1, p331
Academic Journal
This study explores a non-isothermal activated kinetics of the Crystalline to Smectic A (K-SmA) transition of the aligned octylcyanobiphenyl (8CB) liquid crystal. High resolution calorimetric technique was used to study the molecular motion and rearrangement of the 8CB molecules near the K-SmA transition as a function of temperature, rate, and time. In the presence of magnetic field, the transition peak was found to be shifted towards lower temperature by 0.5 K when compared with results of un-magnetized 8CB. The K-SmA transition showed a rate dependent kinetics following Arrhenius behavior where the increased shifting rate showing an increased thermal kinetics for the transition. The 8CB molecules get more aligned and more ordered that pushes the temperature of the transition towards lower temperature in the presence of magnetic field. Hence they show a temperature decrease in the peak of the transition temperature with a decrease in the enthalpy and hence needs more activation energy. This study may be useful to understand the liquid crystal behavior to upgrade liquid crystal devices (LCDs).


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