Electroclinic materials with large induced tilt angles

Abstract

The electroclinic effect in the smectic A phase of three successive even members of a homologous series has been studied. They exhibit large field-induced tilt angles up to 15° for an applied electric field of 10V/b.mum over a wide temperature range. The induced tilt angle increases with increasing alkyl chain length (n) of the non-chiral end of the molecule. On cooling from high temperatures, the induced tilt angle b.thetas initially increases monotonically, but at lower temperatures, the trend is reversed. This observed anomaly is more pronounced for the higher homolog and at higher electric fields. A similar anomaly is also seen in the variation of the electroclinic coefficient evaluated at low fields. The relationship between the electroclinic tilt angle and molecular structure is discussed