Experimental studies of short range order in nematogens of strong positive dielectric anisotropy

Abstract

The magnetic and electric birefringence in the isotropic phase of 4'-n-hexyl4cyanobipheny1, a nematogen of high positive dielectric anisotropy, have been measured as functions of temperature. Both show a (T-T*)-1 dependence in the range .of temperatures studied. We also report the dielectric constants of 4'-n-octyloxy-4-cyanobiphenyl measured in the nematic and isotropic phases. The mean dielectric constant shows a slight increase on passing from the nematic to the isotropic phase. These results are in conformity with the model of antiferroelectric short range order proposed by Madhusudana and Chandrasekhar.