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Dr. Sudhir Kumar Keshri Dr. Atsuro Takai Prof. Dr. Tomoya Ishizuka Prof. Dr. Takahiko Kojima Prof. Dr. Masayuki Takeuchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5292-5296
The design and synthesis of an enantiomeric pair of 1,8-diethynylanthracene-bridged naphthalenediimide (NDI)-based cyclophanes ( Cyclo-NDI s) are reported. Each enantiomer of Cyclo-NDI exhibits a circularly polarized luminescence signal with a relatively large luminescence dissymmetry factor (glum=±8×10−3). We have further investigated the modulation of through-space electronic communication between co-facially oriented NDIs in a discrete Cyclo-NDI with changes in the temperature. Tuning of the electronic communication results from the conformational transformation of monomer- versus dimer-like features of Cyclo-NDI , as confirmed by UV/Vis, fluorescence, circular dichroic, and NMR spectroscopic analysis. The temperature-dependent optical response in the Cyclo-NDI through the conformational transformation could be utilized as a highly sensitive and reversible optical thermometer in a wide temperature range (100 to −80 °C). 相似文献
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Feng Hu Jiao-Jiao Li Zong-Jie Guan Shang-Fu Yuan Prof. Dr. Quan-Ming Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5350-5353
By directly reducing alkynyl–silver precursors, we successfully obtained a large alkynyl-protected silver nanocluster, (C7H17ClN)3[Ag112Cl6(C≡CAr)51], which is hitherto the largest structurally characterized silver nanocluster in the alkynyl family. The cluster exhibits four concentric core–shell structures (Ag13@Ag42@Ag48@Ag9), and four types of alkynyl–silver binding modes are observed. Chloride was found to be critical for the stabilization and formation of the silver nanocluster. The release of chloride ions in situ from CH2Cl2 solvent has been confirmed by mass spectrometry. This study suggests that the combination of alkynyl and halide ligands will pave a new way for the synthesis of large silver nanoclusters. 相似文献
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Tristan S. Kleine Taeheon Lee Kyle J. Carothers Meghan O. Hamilton Laura E. Anderson Liliana Ruiz Diaz Nicholas P. Lyons Keith R. Coasey Wallace O. Parker Ludovico Borghi Michael E. Mackay Kookheon Char Richard S. Glass Dennis L. Lichtenberger Robert A. Norwood Jeffrey Pyun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17820-17824
Optical technologies in the long‐wave infrared (LWIR) spectrum (7–14 μm) offer important advantages for high‐resolution thermal imaging in near or complete darkness. The use of polymeric transmissive materials for IR imaging offers numerous cost and processing advantages but suffers from inferior optical properties in the LWIR spectrum. A major challenge in the design of LWIR‐transparent organic materials is that nearly all organic molecules absorb in this spectral window which lies within the so‐called IR‐fingerprint region. We report on a new molecular‐design approach to prepare high refractive index polymers with enhanced LWIR transparency. Computational methods were used to accelerate the design of novel molecules and polymers. Using this approach, we have prepared chalcogenide hybrid inorganic/organic polymers (CHIPs) with enhanced LWIR transparency and thermomechanical properties via inverse vulcanization of elemental sulfur with new organic co‐monomers. 相似文献