A study of 4 nonanoate, 4'-cyanobiphenyl using dielectric relaxation method

Abstract In this paper, the results of a dielectric absorption study for 4 nonanoate 4’ cyanobiphenyl are presented. For electric field E perpendicular to director n, a very distributed domain can be observed. It can be interpreted as resulting from the superposition of rotation and libration movements of the molecule and of intramolecular movements. For E parallel to n, the reorientational movement of the molecule is observed. The activation energy of this mechanism is lower in SmA phase at T > 30°C than in nematic phase. Moreover, if T < 25°C the activation energy increases. These variations seem to be characteristic of a partially bilayer SmA phase with the appearing of monolayer Sc domains at T < 25°C.