Discotic liquid crystals—columnar and nematic mesophases

During the last 17 years an enormous amount of research into the synthesis of disc-like materials and into the stmcmral characterisation of the discotic mesophases generated has been performed by many research groups throughout the world. Two basic types of discotic mesophases have been widely recognised, these arc columnar and nematic. 

Discotic materials can also generate a nematic phase (designated N ) and, as for calamitic materials, oidy one nematic phase exists. The phase gives an identical 

Now that the basic idea of the stractures of the various discotic mesophases has been considered we can discuss the types of molecular stmctmes that generate such phases. For example, what stractural moieties constitute a suitable molecular architecture for the generation of discotic mesophases Perhaps the term discotic is not strictly appropriate 

The vast majority of discotic materials exhibit columnar phases, some additionally show the phase, and very few exhibit only the phase. The 

The triphenylene core consists of three benzene rings conjugatively joined to give a planar aromatic unit that enables six peripheral units to be symmetrically attached, and because the eore is mueh larger than benzene, the mesomorphic tendency of such compounds is much higher. 

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Discotic liquid crystals—columnar and nematic mesophases... 

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