Relaxation processes in nematic liquid crystals in the nonstationary regime of a rotation of magnetic field

Abstract

The prospects of using the nonstationary regime of motion of the director for studying the relaxation properties of liquid crystals in the low-temperature interval of the nematic phase are shown. In the nonstationary regime, the phase shift between the direction and the wave vector is 45 and does not depend on the angular velocity of rotation of the magnetic field. A eutectic mixture of nematic liquid crystals with a wider temperature range of the nematic phase compared to individual components has been studied. A decrease in the anisotropy of the absorption coefficient in the nonstationary regime is associated with a partial violation of the homogeneous orientation of the sample. The nature of the dependence of the low-frequency component of the phase characteristic on the thermodynamic parameters of the state is established. Within the framework of the hydrodynamics of the nematic phase, relations were obtained that allow calculating the dissipative coefficients responsible for the performance of liquid crystal technical devices.