Dynamical and Structural Characteristics of Biaxial Discotic Mesophases by Deuterium NMR
Discotic liquid crystalline mesophases were discovered about eight years ago, almost simultaneously in India (1) and France (2), Since then several hundreds of compounds and at least seven structurally different classes of such mesophases were identified by optical and X-ray techniques (3,4). In recent years we extended these studies using in particular deuterium NMR of labelled mesogens or dissolved probe molecules. These studies provided information on orientational order, conformational equilibria and solute-solvent interaction in the various discotic mesophases. More recently we concentrated our attention on biaxial discotics and in the present contribution we describe results related to their structural and dynamic characteristics. Before describing these results in more detail we briefly review the chemical characteristics and classification of discotic liquid crystals (4).
KeywordsNematic Phase Jump Diffusion Discotic Liquid Crystal Mesophases Columnar High Molecular Complexity
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