INDUCTION OF SMECTIC-A PHASES AND CUBIC PHASES IN BINARY-SYSTEMS OF NEW HEXACATENAR SUBSTANCES

It is shown that in binary systems of hexacatenar (phasmidic) compound s with relatively short rod-shaped compounds smectic A phases can be i nduced provided that the rod-like component acts as an electron accept or and the hexacatenar compound is a weak electron donator. According to X-ray investigations the stabilization of the smectic layer structu re is due to the incorporation of the short rod-like molecules within the gaps between the terminal branches of the phasmidic molecules. In two binary systems the phase region of the induced smectic A phase and the region of the columnar phase is separated by an induced cubic pha se.