Fluorescent materials find numerous applications in light-based devices, but their utilization is severely affected by concentration caused quenching of fluorescence, the extreme form of which is the total loss of fluorescence in the solid state. Introduction of bulky substituents remains the most frequently applied fluorescence revival strategy, but requires multi-step synthetic modifications. We have demonstrated a simple one step supramolecular gel-based strategy to preserve the fluorescence in the solid state.
View Article and Find Full Text PDFExtensive efforts have been dedicated towards designing new organic materials that display solid-state fluorescence and possess optical activity, thereby leading to the fabrication of materials emitting circularly polarized light. Existing organic materials usually suffer from two limitations, a low dissymmetry factor () and weak or no fluorescence in the solid state. Herein, we have demonstrated a naphthalene imide-based dyad system that remains fluorescent even in powder form and displays circularly polarized luminescence in its aggregated and solid state with significantly high values.
View Article and Find Full Text PDFMono- and bis-salen functionalised [2]rotaxanes have been synthesised from the esterification of [2]rotaxanes containing phenol-terminated threads (salen=N,N'-bis(salicylidene)ethylenediamine). The [2]rotaxanes have general formula [RH][CrNiF(OCBu)], where [RH] is a thread with a central secondary ammonium site that templates a [CrNiF(OCBu)] ring. The threads are terminated at one or both ends by carboxylic acid functionalised salen groups.
View Article and Find Full Text PDFHere we report the synthesis and structural characterization of four [7]rotaxanes formed by coordinating hybrid inorganic-organic [2]rotaxanes to a central {Ni} core. X-ray single crystal diffraction demonstrate that [7]rotaxanes are formed, with a range of conformations in the crystal. Small angle X-ray scattering supported by molecular dynamic simulations demonstrates that the large molecules are stable in solution and also show that the conformers present in solution are not those found in the crystal.
View Article and Find Full Text PDFFor the molecular properties in which energy transfer/migration is determinantal, such as triplet-triplet annihilation-based photon up-conversion (TTAUC), the overall performance is largely affected by the intermolecular distance and relative molecular orientations. In such scenarios, tools that may steer the intermolecular interactions and provide control over molecular organisation in the bulk, become most valuable. Often these non-covalent interactions, found predominantly in supramolecular assemblies, enable pre-programming of the molecular network in the assembled structures.
View Article and Find Full Text PDF