COLUMNAR MESOPHASES FROM NONDISCOID METALLOMESOGENS - RHODIUM AND IRIDIUM DICARBONYL DIKETONATES

A series of nondiscoid rhodium and iridium dicarbonyl beta-diketonate complexes have been shown to organize in columnar liquid crystal phase s with hexagonal disordered structures (Col(hd)). The shape and dipola r attributes of these materials produce highly correlated antiparallel pairwise arrangements. This organization was investigated by X-ray di ffraction and miscibility studies. The liquid crystallinity was found to be stabilized by decreasing the number of carbon atoms in the side chains, and single component room-temperature liquid crystals were dev eloped. The nature of the metal is also important, and iridium mesogen s exhibited higher clearing points than the analogous rhodium material s.