Appearance of the Induced Smectic A Phase in the Binary System between Two Troponoid Twins with the Opposite Dipole Moment

A new troponoid twin system, in which two tropone carbonyl groups direct outside, was prepared, but they were not mesogenic. The binary system between the new twins and the troponoid twins with the two tropone carbonyl groups directed inside, which had a monotropic smectic C phase, showed an induced enantiotropic smectic A phase. From the X-ray diffraction study of the binary systems, a molecular packing model perpendicular to the lamellar planes was proposed, in which the dipole moments of tropone rings were canceled.