Sculpting Mesoscopic Helical Chirality into Covalent Organic Framework Nanotubes from Entirely Achiral Building Blocks

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(3)

Published: Nov. 28, 2023

Abstract The diversification of chirality in covalent organic frameworks (COFs) holds immense promise for expanding their properties and functionality. Herein, we introduce an innovative approach imparting helical to COFs fabricating a family chiral COF nanotubes with mesoscopic helicity from entirely achiral building blocks the first time. We present effective 2,3‐diaminopyridine‐mediated supramolecular templating method, which facilitates prefabrication imine‐linked polymer using unprecedented symmetric monomers. Through meticulous optimization crystallization conditions, these are adeptly converted into boasting impressive surface areas, while well preserving morphology chiroptical properties. Furthermore, polymers or could be subtly transformed corresponding more stable functional β‐ketoenamine‐linked hydrazone‐linked transferred circular dichroism via monomer exchange. Notably, despite involvement bonding breakage reorganization, exchange processes overcome thermodynamic disadvantages, allowing perfectly preserved. This research highlights potential conferring favourable properties, providing novel insights development multifunctional field materials chemistry.

Language: Английский

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Halogen bonding–driven chiral amplification of a bimetallic gold-copper cluster through hierarchical assembly

Science Advances, Journal Year: 2023, Volume and Issue: 9(47)

Published: Nov. 22, 2023

Understanding the fundamentals and applications of chirality relies substantially on amplification through hierarchical assemblies involving various weak interactions. However, a notable challenge remains for metal clusters chiral assembly driven by halogen bonding, despite their promising in lighting, catalysis, biomedicine. Here, we used bonding-driven to achieve degree achiral emissive Au2Cu2 clusters. From single crystals one-dimensional ribbons then helixes, morphologies were primarily modulated intermolecular bonding that evoked or/and iodofluorobenzene (IFBs) molecules. Concomitantly, luminescence circularly polarized (CPL) changed lot, ultimately leading substantial increase dissymmetry g-factor (glum) 0.036 supramolecular helix. This work opens an avenue using predesigned as building blocks though directional bonding. achievement marks noteworthy advancement field nanosized inorganic functional blocks.

Language: Английский

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Spatiotemporal Programmability of 3D Chiral Color Units Driven by Ink Spontaneous Diffusion toward Customized Printing

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 19, 2024

Abstract Blue phase liquid crystals (BPLCs) have exhibited promising applications in 3D flexible displays due to their molecular‐level self‐assembled chiral structures, fast response, and tunable polarized colors. However, there remain challenges for spatiotemporal programming of color units BPLC dynamic patterning. Herein, the programmable temporal evolution micrometer‐scale spatial configuration switch modes are achieved by spontaneous ink diffusion‐driven asymmetric lattice deformation dual‐chiral polymer‐templated blue phases. Custom‐printed colorful patterns designed machine learning‐assisted parameter optimization, which multidimensional encrypted information that incorporates evolving colors (wavelength), distribution (depth), (L/R). The quantitative relationship between diffusion kinetics blue‐phase structural optics is established situ characterization, finite element analysis, mathematical geometry modeling. This work provides insights into microgeometric manipulation BPLCs application security self‐adaptive indicators.

Language: Английский

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Finely tuning the self-assembled architectures of liquid crystal polymers by molecular engineering: phase transitions derived from terminal group variations

Materials Advances, Journal Year: 2024, Volume and Issue: 5(8), P. 3450 - 3458

Published: Jan. 1, 2024

Through rational molecular design and modulation of terminal groups in building blocks, as an efficient approach, it is quite to achieve diverse phase transition behaviours adjust structures.

Language: Английский

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Tuning the Properties of Hydrazone/Isosorbide-Based Switchable Chiral Dopants

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(35), P. 24561 - 24569

Published: Aug. 20, 2024

The long-range supramolecular interactions in liquid crystals (LCs) can be used to amplify and subsequently propagate microscopic structural changes into macroscopic events. Here, we report on a systematic structure–property analysis using 16 chiral photoswitchable dopants composed of bistable hydrazones isosorbide moieties. Our findings showcase the relationship between dopant's structure its helical twisting power (β), hence, photophysical properties host LC. We show that an increase hydrazone CNNH dihedral angle results β value, while alkoxy chains do not lead such increase. These contradict established rules thumb, stating rigidity long alky are needed for high values. also found position substitution, whether at 2′ or 5′ positions unit, attachment unit rotor stator phenyl units have negative positive additive effects either decrease made us hypothesize unsymmetrically functionalized should result large Δβ values, which corroborated experimentally. Moreover, fluorine-functionalized dopant resulted higher overall most likely because π–π interactions. Finally, were modulating locking reflective LC films, yielding multicolor canvases reflect light from ultraviolet infrared range (i.e., manipulation up ca. 1500 nm reflected light).

Language: Английский

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