Synthesis, mesogenic and dielectric properties of fluorosubstituted isothiocyanatoterphenyls

The synthesis, mesomorphic and physical properties of 14 homologous series of laterally fluorinated 4ʹ-alkyl-4-isothiocyanatoterphenyls were described. Influence of the number of fluorine atoms and their position in the terphenyl core on the phase transition temperatures, nematic range, dielectric and optic anisotropy as well as bulk viscosity were discussed. The compounds with the most optimal properties for formulation of nematic mixtures were selected, and mixture examples with low viscosity and medium or high birefringence were presented.