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The synthesis, optical properties and thermal behaviour of three novel non-conventional 3,4,9,10-tetrasubstituted perylene-based discotic oligomers are reported for the first time consisting of a perylene core attached to which are four 4-cyanobiphenyl, triphenylene and cholesteryl units via flexible alkyl spacers. All the oligomers self-assemble into a mesophase and exhibit excellent fluorescence emission properties making them suitable for various opto-electronic applications.

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This paper advances the design of stimuli-responsive materials based on colloidal particles dispersed in liquid crystals (LCs). Specifically, we report that thin films of colloid-in-liquid crystal (CLC) gels can undergo easily visualized ordering transitions in response to reversible and irreversible (enzymatic) biomolecular interactions occurring at aqueous interfaces of the gels. In particular, we demonstrate that LC ordering transitions can propagate across the entire thickness of the gels. We observe, however, that confinement of the LC to small domains with lateral sizes of ~10 µm does change the nature of the anchoring transitions, as compared to films of pure LC, due to the effects of confinement on the elastic energy stored in the LC. The effects of confinement are also observed to cause the response of individual domains of the LC within the CLC gel to vary significantly from one another, indicating that manipulation of LC domain size and shape can provide the basis of a general and facile method to tune the response of these LC-basedphysical gels to interfacial phenomena. Overall, the results presented in this paper establish that CLC gels offer a promising approach to the preparation of self-supporting, LC-based stimuli-responsive materials.

Four discotic liquid crystals (DLCs) based on anthracene, a novel redox active central core, have been synthesized and their mesomorphic behavior investigated. Among them, two of the derivatives showed stable hexagonal plastic mesophases whereas other two exhibited a columnar nematic phase at near room temperature as derived by X-ray scattering results. Type of the mesophases formed by these new class of compounds are rare that renders the central anthracene core attractive in the search for new functional DLC materials. HOMO-LUMO val-ues have also been found to be much less in these materials which make them as good candidates for electron migration studies in self-organized systems. All the compounds show blue luminescence in solution under the long wavelength UV light. Overall, these new class of materials are promising, considering the emissive nature, ease of synthesis and stabilization of unconventional mesophases at room temperature or near room temperature.