Analysis of Space Charge Polarization of 4-cyano-4'-n-pentylbiphenyl (5CB) in a nematic phase

Abstract

The complex dielectric constant of 4-n-pentyl-4'-cyanobiphenyl (5CB) was measured between 0.0001Hz and 1kHz in nematic and isotropic phases. The dielectric dispersion due to space-charge polarization was observed for both phases. The diffusion coefficient D and the mobility μ and the number density n of ions in 5CB were determined in the analysis of the experimental result. In a nematic phase, the anisotropy of the μ was estimated by controlling the molecular orientation under a magnetic field. Furthermore, the relationship between the mobility and the viscosity coefficients of 5CB was investigated.