New 1,3-dithiane type ionic liquid crystal compounds

New pyridinium type thermotropic ionic liquid crystal materials having a 1,3-dithiane ring in their central core, N -substituted-4-(5-alkyl-1,3-dithian-2-yl)pyridinium bromides ( 8 ), were synthesized. These compounds exhibited a smectic A phase over a very wide temperature range including room temperature.