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Use of abiotic chemical systems for understanding higher order superstructures is challenging. Here we report a ring‐in‐ring(s) system comprising a hydrogen‐bonded macrocycle and cyclobis(paraquat‐o‐phenylene) tetracation (o‐Box) or cyclobis(paraquat‐p‐phenylene) tetracation (CBPQT4+, p‐Box) that assembles to construct discrete higher order structures with adaptive conformation. As indicated by mass spectrometry, computational modeling, NMR spectroscopy, and single‐crystal X‐ray diffraction analysis, this ring‐in‐ring(s) system features the box‐directed aggregation of multiple macrocycles, leading to generation of several stable species such as H4G (1 a/o‐Box) and H5G (1 a/o‐Box). Remarkably, a dimeric shish‐kebab‐like ring‐in‐rings superstructure H7G2 (1 a/o‐Box) or H8G2 (1 a/p‐Box) is formed from the coaxial stacking of two ring‐in‐rings units. The formation of such unique dimeric superstructures is attributed to the large π‐surface of this 2D planar macrocycle and the conformational variation of both host and guest. [ABSTRACT FROM AUTHOR]

Despite vast applications of macrocycles in supramolecular chemistry, achieving long‐lived emissions including room‐temperature phosphorescence (RTP) or thermally activated delayed fluorescence (TADF) for potential use still presents a great challenge. This work first reports hydrogen‐bonded (H‐bonded) macrocycles emitting RTP and TADF by introducing various donors onto the same aramide skeleton containing a rigid acceptor. The formation of charge transfer effectively enhances the photoluminescence efficiency. Aromatic carbonyl groups promote the intersystem crossing. The drastically reduced flexibility of chromophores fixed by the H‐bonded macrocyclic framework contributes to suppress the nonradiative decay to stabilize triplet excitons. Therefore, RTP and TADF are acquired by altering donors, and are systematically revealed by comparisons with control compounds and theoretical calculations. Finally, near white‐light emission (CIE, 0.30, 0.33) is realized via host–guest interactions. [ABSTRACT FROM AUTHOR]

Community detection in social networks attracts a lot of attention in the recent years. Existing methods always depict the relationship of two nodes using the temporary connection. However, these temporary connections cannot be fully recognized as the real relationships when the history connections among nodes are considered. For example, a casual visit in Facebook cannot be seen as an establishment of friendship. Hence, our question is the following: how to cluster the real friends in mobile social networks? In this paper, we study the problem of detecting the stable community core in mobile social networks. The cumulative stable contact is proposed to depict the relationship among nodes. The whole process is divided into timestamps. Nodes and their connections can be added or removed at each timestamp, and historical contacts are considered when detecting the community core. Also, community cores can be tracked through the incremental computing, which can help to recognize the evolving of community structure. Empirical studies on real-world social networks demonstrate that our proposed method can effectively detect stable community cores in mobile social networks. [ABSTRACT FROM AUTHOR]