A molecular crystal of a 2-D hydrogen-bonded organic framework (HOF) undergoes an unusual structural transformation after solvent removal from the crystal pores during activation. The conformationally flexible host molecule, , adapts its molecular conformation during activation to initiate a framework expansion. The microcrystalline activated phase was characterized by three-dimensional electron diffraction (3D ED), which revealed that uses out-of-plane anthracene units as adaptive structural anchors. These units change orientation to generate an expanded, lower density framework material in the activated structure. The porous HOF, , has robust dynamic porosity (SA = 1183 m g) and exhibits negative area thermal expansion. We use crystal structure prediction (CSP) to understand the underlying energetics behind the structural transformation and discuss the challenges facing CSP for such flexible molecules.
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http://dx.doi.org/10.1021/jacs.0c04885 | DOI Listing |
Adv Mater
January 2025
Department of Hepatobiliary Surgery, Eastern Hepatobiliary Surgery Hospital, Naval Medical University, Shanghai, 200438, P. R. China.
X-ray induced photodynamic therapy (X-PDT) leverages penetrating X-ray to generate singlet oxygen (O) for treating deep-seated tumors. However, conventional X-PDT typically relies on heavy metal inorganic scintillators and organic photosensitizers to produce O, which presents challenges related to toxicity and energy conversion efficiency. In this study, highly biocompatible organic phosphorescent nanoscintillators based on hydrogen-bonded organic frameworks (HOF) are designed and engineered, termed BPT-HOF@PEG, to enhance X-PDT in hepatocellular carcinoma (HCC) treatment.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
College of Chemistry, Sichuan University, Chengdu 610064, China.
Circularly polarized luminescence (CPL) is an emerging field with significant applications in molecular electronics, optical materials, and chiroptical sensing. Achieving efficient CPL emission in organic systems remains a major challenge, particularly in the development of materials with high fluorescence quantum yields (Φ) and large luminescence dissymmetry factors (g). Herein, we report the efficient synthesis of shape-persistent tetraphenylethylene macrocycles and investigate its potential as a CPL material.
View Article and Find Full Text PDFMolecules
December 2024
Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Hydrogen-bonded organic framework (HOF) materials are typically formed by the self-assembly of small organic units (synthons) with specific functional groups through hydrogen bonding or other interactions. HOF is commonly used as an electrolyte for batteries. Well-designed HOF materials can enhance the proton exchange rate, thereby boosting battery performance.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
UM-DAE Centre for Excellence in Basic Sciences, Kalina Campus of Mumbai University, Santacruz (E), Mumbai 400098, India.
Excited-state proton transfer (ESPT) in organic photoacids is a widely studied phenomenon in which D-luciferin is of special mention, considering the fact that apart from its phenolic OH group, the nitrogen atoms at either of the two thiazole moieties could also participate in hydrogen bonding interactions with a proton-donating solvent during ESPT. As a result, several transient species could appear during the ESPT process. We hereby deploy subpicosecond time-resolved fluorescence upconversion (FLUP) and transient absorption (TA) spectroscopic techniques to understand the detailed photophysics of D-luciferin in water as well as in dimethyl sulfoxide (DMSO) and ethanol.
View Article and Find Full Text PDFSmall
January 2025
Xi'an Key Laboratory of Functional Organic Porous Materials, Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710129, P. R. China.
Self-assembly in supramolecular chemistry is crucial for nanostructure creation but faces challenges like slow speeds and lack of reversibility. In this study, a novel comb-like polymer poly(amide sulfide) (PAS) based on thiolactone chemistry is reported, which rapidly self-assemble into stable nanofibers, offering excellent robustness and reversibility in the self-assembled structure. The PAS backbone contains pairs of amide bonds, each linked to an alkyl side chain in a controlled 2:1 ratio.
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