X-Ray Studies of Two Liquid Crystalline Compounds

Abstract

X-ray studies of two liquid crystalline compounds, viz., p-ethoxybenzylidene p-heptylaniline (2O.7) and p-butoxybenzylidene p-heptylaniline (4O.7) are reported in this paper. The compound 2O.7 shows only a nematic phase while 4O.7 exhibits SmB, SmC, SmA, and nematic phases. Using powder X-ray diffraction patterns recorded at different temperatures, the microstructural parameters, and pair correlation function of these compounds have been estimated. The results obtained are inferred in terms of molecular ordering present in their nematic and smectic phases.

Keywords:

• Liquid crystals
• microstructural parameters
• 2O.7
• 4O.7
• pair correlation function
• X-ray diffraction

Acknowledgments

Authors acknowledge Dr. R. Pratibha, Mrs. Deepa Bhat, and Mrs. K. N. Vasudha, Raman Research Institute (RRI), Bangalore, for their assistance in the collection of X-ray data. Author M.K.U. acknowledges the Department of Science and Technology (DST), New Delhi for the award of INSPIRE fellowship. N.V. is grateful to the University Grants Commission (UGC), New Delhi for the award of RFSMS fellowship. D.R. is thankful to the UGC for financial support under Major Research Project Scheme [F.No.41-882/2012 (SR)]. Authors R.S. and D.R. acknowledge UGC, New Delhi for funding under UPE project.