Abstract
We report detailed results of optical rotatory power (ORP), slective reflection (SR), refractive index anisotropy (RIA), and anisotropic Rayleigh scattering (ARS) measurements in the antiferroelectric liquid crystal, 4-(1-methylheptyl-oxycarbonyl) phenyl-4’octyloxy phenyl-4-carboxylate (MHPOBC). The ORP in Sm-A and Sm- phases has been found to be zero or at least very weak compared to ordinary liquids with strongly chiral molecules. No helical pitch is observed in the Sm-A, Sm- and Sm- phases in the range 200–2200 nm. The combined use of ORP and SR allows the precise determination of the tilt angle of the smectic-C phases. Obtained values are found to be in good agreement with both theoretical calculations and experimental results obtained from RIA. Moreover, ARS reveals the local biaxial character of the Sm- phase, while the absence of critical behavior of the Sm-A∥Sm- phase transition is a direct proof of the lack of biaxiality in the Sm- phase.
- Received 1 March 1995
DOI:https://doi.org/10.1103/PhysRevE.52.1846
©1995 American Physical Society