The physical and molecular properties of new low melting nematics with negative dielectric anisotropy

The paper presents some basic physical properties (static electric permittivities, refraction indices, density and viscosity) of 2-chloro-4-n'-alkylphenyl esters of 4-n-alkylbicycio[2,2,2]octane-1-carboxylic acids (n' = 7, n = 5 and 7) which are, at room temperature, nematics with a negative dielectric anisotropy. On the basis of temperature dependence of the principal static permittivities epsilon(\\)(T) and epsilon(perpendicular to)(T) of the nematics, using the Maier-Meier equations, the angle between the dipole moment vector and the long axis of mesogenic molecules, the al,parent molecular dipole moment square mu(app)(2)(T), and the nematic order parameter S (T) were determined.