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Lanthanide-derived materials are promising candidates for efficient circularly polarized luminescence (CPL) with a high dissymmetry factor (glum). However, synthesizing chiral ligands in lanthanide-based designs remains challenging. In this context, we present a simpler, modular approach using 'supramolecular chirality induction' and non-covalent sensitization to create soft hydrogel materials with tunable CPL emission and a remarkably high glum of 2 × 10−2. [ABSTRACT FROM AUTHOR]

Temporal control over self-assembly processes is a highly desirable attribute that is efficiently exhibited by biological systems, such as actin filaments. In nature, various proteins undergo enzymatically catalysed chemical reactions that kinetically govern their structural and functional properties. Consequently, any stimuli that can alter their reaction kinetics can lead to a change in their growth or decay profiles. This underscores the urgent need to investigate bioinspired, adaptable and controllable synthetic materials. Herein we intend to develop a general strategy for controlling the growth and decay of self-assembled systems via enzymatically coupled reactions. We achieve this by the coupling of enzymes phosphokinase/phosphatase with a bolaamphiphilic cationic chromophore (PDI) which selectively self-assembles with ATP and disassembles upon its enzymatic hydrolysis. The aggregation process is efficiently regulated by the controlled in situ generation of ATP, through enzymatic reactions. By carefully managing the ATP generating components, we realize precise control over the self-assembly process. Moreover, we also show self-assembled structures with programmed temporal decay profiles through coupled enzymatic reactions of ATP generation and hydrolysis, essentially rendering the process dissipative. This work introduces a novel strategy to generate a reaction-coupled one-dimensional nanostructure with controlled dimensions inspired by biological systems. [ABSTRACT FROM AUTHOR]

In this study, we efficiently sensitize pyromellitic diimide's triplets by cocrystallizing with heavy bromine-substituted small aromatics. The resulting halogen bonding interactions mediate an external heavy atom effect, leading to remarkable ambient phosphorescence with one of the highest quantum yields reported to date. [ABSTRACT FROM AUTHOR]

Triplet state modification in organic phosphorescence molecules for a desired color and quantum yield is typically pursued by chemical modification. A facile methodology is introduced to tune the triplet state dynamics of a phosphorescent molecule by changing the host‐matrix parameters. An organic phosphor, Br2PmDI (2–Bromo pyromellitic diimide), dispersed at dilute levels (1.5 wt.%) in a semicrystalline high‐κ relaxer ferroelectric host matrix emit room‐temperature phosphorescence accompanied by a delayed fluorescence component. The host relaxer ferroelectric polymer film can be engineered to form a photonic matrix with a regular micropore structure of refractive index contrast ≈0.6 that can increase the density of optical states and introduce photonic coupling. The phosphorescence quantum yield of Br2PmDI in this photonic matrix increases by ≈2.3 fold, and the lifetime reduces by a factor of three. The coupled quantum states are investigated by time‐resolved spectroscopy at different temperatures and pump intensities. [ABSTRACT FROM AUTHOR]

Self-assembly provides an attractive route to functional organic materials, with properties and hence performance depending sensitively on the organization of the molecular building blocks (1-5). Molecular organization is a direct consequence of the pathways involved in the supramolecular assembly process, which is more amenable to detailed study when using one-dimensional systems. In the case of protein fibrils, formation and growth have been attributed to complex aggregation pathways (6-8) that go beyond traditional concepts of homogeneous (9-11) and secondary (12-14) nucleation events. The self-assembly of synthetic supramolecular polymers has also been studied and even modulated (15-18), but our quantitative understanding of the processes involved remains limited. Here we report time-resolved observations of the formation of supramolecular polymers from π-conjugated oligomers. Our kinetic experiments show the presence of a kinetically favoured metastable assembly that forms quickly but then transforms into the thermodynamically favoured form. Quantitative insight into the kinetic experiments was obtained from kinetic model calculations, which revealed two parallel and competing pathways leading to assemblies with opposite helicity. These insights prompt us to use a chiral tartaric acid as an auxiliary to change the thermodynamic preference of the assembly process (19). We find that we can force aggregation completely down the kinetically favoured pathway so that, on removal of the auxiliary, we obtain only metastable assemblies., The π-conjugated oligomer S-chiral oligo(p-phenylenevinylene) (SOPV, Fig 1a) serves as a functional material in a variety of organic electronic devices, with performance critically dependent on the material's morphology (20). This [...]