Static and dynamic dielectric polarization and viscosity of n-hexylcyanobiphenyl in the isotropic and nematic phases

On the basis of the temperature dependence of the static principal permitti vities, epsilon (parallel to) and epsilon (perpendicular to), measured for the nematic phase of n-hexylcyanobiphenyl (C6H13-Ph-Ph-C=N, 6CB), a value o f the angle beta between the long molecular axis and the direction of the d ipole moment mu of 6CB, as well as the order parameter S(T), were obtained by use of the Maier-Meier equations. From the dielectric relaxation and vis cosity data, the contribution of the nematic potential to the molecular dyn amics was estimated. In the isotropic phase the dielectric and viscosity da ta allow one, in the framework of the Debye model, to estimate the effectiv e length of 6CB molecule.