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Realizing dual charge transfer (CT) based on stable organic radicals in one system is a long‐sought goal, however, remains challenging. In this work, a stable mixed‐valence radical crystal is designed via a surfactant‐assisted method, namely TTF‐(TTF+•)2‐RC (where TTF = tetrathiafulvalene), containing dual CT interactions. The solubilization of surfactants enables successful co‐crystallization of mixed‐valence TTF molecules with different polarity in aqueous solutions. Short intermolecular distances between adjacent TTF moieties within TTF‐(TTF+•)2‐RC facilitate both inter‐valence CT (IVCT) between neutral TTF and TTF+•, and inter‐radical CT (IRCT) between two TTF+• in radical π‐dimer, which are confirmed by single‐crystal X‐ray diffraction, solid‐state absorption, electron spin resonance measurements, and DFT calculations. Moreover, TTF‐(TTF+•)2‐RC reveals an open‐shell singlet diradical ground state with the antiferromagnetic coupling of 2J = −657 cm−1 and an unprecedented temperature‐dependent magnetic property, manifesting the main monoradical characters of IVCT at 113–203 K while the spin‐spin interactions in radical dimers of IRCT are predominant at 263–353 K. Notably, dual CT characters endow TTF‐(TTF+•)2‐RC with strong light absorption over the full solar spectrum and outstanding stability. As a result, TTF‐(TTF+•)2‐RC exhibits significantly enhanced photothermal property, an increase of 46.6 °C within 180 s upon one‐sun illumination. [ABSTRACT FROM AUTHOR]

[3]Radialene has a peculiar topology and cross‐conjugation system, representing a unique molecular scaffold in organic materials. Herein, we report a special class of stereoisomeric α‐cyano triaryl[3]radialenes (CTRs) that show concentration‐caused quenching in solution but emit red‐shifted and enhanced luminescence in the crystalline state. Clustering of multiple cyano groups and their through‐space interactions with the [3]radialene ring significantly extend π‐electron communication meanwhile rigidifying the propeller conformation multivalently, thus playing a key role behind the state‐dependent luminescence. These radialenes with a substantial electron affinity undergo a reversible electron transfer transition to anionic radicals with good stability, showing switching of photoabsorption, photoluminescence and electron spin resonance (ESR) signal. We also established proof‐of‐concept applications of CTRs for multimodal information encryption and chemical sensing. [ABSTRACT FROM AUTHOR]

Dynamic materials undergoing adaptive solid‐state transitions are attractive for soft mechanics and information technology. Here, we report a novel porous framework system based on macrocyclic trimers assembled from open‐shell tetraarylethylene building blocks with aryldicyanomethyl radicals as coupling linkers. Under mechanical, thermal, or chemical stimuli, the framework showed adaptability by activating conformational dynamics and radical‐based transformations, thus displaying macroscopic responsiveness in terms of light absorption, luminescence, and magnetism. We studied the dynamic processes by variable‐temperature nuclear magnetic resonance (VT‐NMR), variable‐temperature electron spin resonance (VT‐ESR), and superconducting quantum interference device (SQUID) measurement and further established a proof‐of‐concept application for multi‐modal information encryption. The strategy may open avenues for rational design of solid‐state photoelectromagnetic dynamic materials by merging dynamic covalent coupling chemistry and functional aggregation principles. [ABSTRACT FROM AUTHOR]