Liquid Crystals in Confining Geometries

Abstract

The properties of liquid-crystalline (LC) phases under submicrometer geometrical confinement can change substantially with respect to bulk samples. We give an overview over studies of the structure and dynamics of confined LC phases. Systems with different adsorber geometries and sizes are compared. Studies of the molecular and collective dynamics of nematic and smectic phases have been performed by means of dielectric and NMR spectroscopy. The experimental results show that the confinement, even in nanometer pores, leaves the molecular dynamics rather uninfluenced. On the other hand, the collective dynamic modes are sensible to pore geometries and sizes already in micrometer pore systems. Moreover, we discuss restricted-volume effects on the phase transitions, and the director configurations and electro-optical properties of nematics in regular and random pore systems.