Abstract
The binary mixture of two nonmesogenic compounds viz., Tetradecyl Trimethyl Ammonium Bromide (TTAB) and Orthophosphoric acid (H3PO4) exhibits very interesting liquid crystalline smectic phases at large range of concentrations and temperature. The mixture with lower and higher concentrations of TTAB exhibits Sm A, Sm D, Sm B, and Sm E phases, sequentially when the specimen is cooled from its isotropic phase. Different liquid crystalline phases observed in the mixture were studied using DSC, X-ray, and Optical microscopic techniques. The temperature variation of optical anisotropy has also been discussed. Helfrich potential and elastic moduli have been estimated in the smectic phase using Helfrich model.
Acknowledgments
HRS would like to thank the University Grants Commission, India, for the financial assistance under MRP scheme [MRP(S)-798/10-11/KAMY022/GUGC-SWRO]. Assistance from Dr. J. Mahadeva and Dr. P. M. Sathyanarayana in carrying the experimental observations is also acknowledged.