Raman scattering study of phase biaxiality in a thermotropic bent-core nematic liquid crystal.

School of Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA.
Physical Review Letters (Impact Factor: 7.73). 07/2010; 105(2):027801. DOI: 10.1103/PhysRevLett.107.109801
Source: PubMed

ABSTRACT Polarized Raman spectroscopy was used to investigate the development of orientational order and the degree of phase biaxiality in a bent-core mesogenic system. The values of the uniaxial order parameters and , and biaxial order parameters , , and , and their evolution with temperature were determined. The temperature dependence of almost all order parameters reveals a second order transition from the uniaxial to biaxial nematic phase with increasing to ∼0.22 before a first order transition to the smectic-C phase, upon cooling.

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May 28, 2014