Correlation between Electrical Properties and Optical Behaviour of Nematic Liquid Crystals

Abstract The results of simultaneous electrical and optical investigations in p-azoxyanisole and di-n-heptoxy-azobenzene are presented. The role of fluid flows is discussed in connection with their importance for domain formation. The mechanism of domain formation and turbulence occurrence is found to be different for d.c. and very low frequencies than it is for higher frequencies. For strong electric fields the behaviour of azoxyanisole is very different from that of the azo compound, a fact attributed to the different sign of the dielectric anisotropy.