Magnetic Alignment and Diamagnetic Anisotropy of Cholesteric Liquid Crystalline Poly-γ-Ethyl-L-Glutamate

Abstract

Abstract The axes of the cholesteric structure of liquid crystalline PELG solution in ethyl acetate tend to be perpendicular to a direction of magnetic field, so that the solution becomes anisotropic in the presence of an applied field. The torque exerted on such anisotropic solutions was measured by appling a magnetic field in a different direction from the original field used for alignment of the cholesteric axes. The anisotropy of diamagnetic susceptibility of the cholesteric structure and that of PELG molecule are estimated from the strength of the torque. The latter is larger than 1.64 × 10-8 emu/g. The average magnetic susceptibilities of PBLG, PEDG and PMLG in the solid state were also measured. These values are in good agreement with those calculated using Pascal's additivity rule.