| Abstract: | The preparation and thermal properties of homologous series of 4-alkoxyphenyl 3-fluoroand 3-methyl-4-thiocyanatophenyl terephthalates are described. Both homologous series show nematic phases; smectic A and C phases are also formed in the higher homologous. The methyl group and fluorine atom adjacent to the thiocyanate group lower the clearing points, in comparison with the unsubstituted compounds. The layer structures for both smectic A and C phases were characterized by X-ray diffraction experiments. The effects of the substituents on liquid crystalline properties are discussed. |
