Liquid-crystalline behaviour of some bis(4-alkyloxyphenyl) thiazolo [5,4-d] dithiazoles

Abstract

The preparation of liquid-crystalline 2,5-bis(4-alkyloxyphenyl) thiazolo [5,4-d] dithiazoles (ATT _n ), in which the alkyl group is C _n H_{2n + 1} (where n = 1 to 10, 12), has been described. Mesomorphic properties and phase transitions as determined by polarizing hot stage microscopy and differential scanning calorimetry are discussed as a function of the number of carbon atoms in the alkyloxy chain. The exhibition of tilted smectic phases (smectic C and smectic I) by these compounds is an interesting feature since there is no significant central dipole moment transverse to these molecules.