The anisotropic properties of a terbium-based liquid crystal complex

Abstract

The dielectric properties of a paramagnetic terbium-containing liquid crystal have been studied. The magnitude and the sign of the dielectric of the liquid crystalline complex have been determined. The relaxation processes (modes) characterizing the dispersion of the principal values of the sample's dielectric permittivity has been studied. The relaxation times, activation energy and the dipole moment of the complex could be evaluated.

Effect of Magnetic and Electric Field on the Orientation of Rare-Earth-Containing Nematics

“…Dielectric permittivities of all the samples were, therefore, measured with the applied voltage U = 1 V, which does not exceed the Freedericksz transition threshold. 84 Taking into consideration that the director of LC complexes may be unaligned with the magnetic field, 19 the angular behavior of dielectric permittivity components was studied at the temperature that corresponds to the existence of the nematic mesophase to eliminate a possible experimental error (Figure 10 and Figure S2). The samples were aligned macroscopically by a magnetic field of 5000 Oe.…”

“…For all the samples of the lanthanide complexes, it was found that applied electric voltages below 2.5 V do not make a substantial contribution to their alignment (Figure S1). Dielectric permittivities of all the samples were, therefore, measured with the applied voltage U = 1 V, which does not exceed the Freedericksz transition threshold …”

“…The measurement cell was a flat titanium capacitor with 12 pF capacity and d = 200 μm distance between electrodes. Capacities were found with a HIOKI-3532 RLC-meter . Dielectric permittivity components in the 100 Hz to 5 MHz electric field frequency range were determined from the reference set of dielectric permittivity values corresponding to the computer-set frequencies.…”