LIQUID-CRYSTALLINE PERYLENE DERIVATIVES - ORIENTATION AND PHASE VARIATION OF DISCOTIC DYES

Discotic liquid-crystalline perylene derivatives can be oriented in the magnetic field far below their clearing temperatures as shown by H-2 solid-state n.m.r. spectroscopy. A mechanical orientation of these materials was achieved by drawing fibers, which were investigated by X-ray diffraction. In addition, it is shown that not only the melting and clearing temperatures, but also the structure of the mesophases depend sensitively on the substitution pattern. The type of liquid crystalline phase can be varied from discotic to smectic.