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Updated: Feb 2, 2026
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Reversible on-off switching of both spin crossover and single-molecule magnet behaviours via a crystal-to-crystal
1State Key Laboratory of Coordination Chemistry , Collaborative Innovation Center of Advanced Microstructures , School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , 210023 , China .
Abstract:
The on-off switching of spin-crossover (SCO) and single-molecule magnetism (SMM) remains highly attractive, especially if it involves dynamic crystal-to-crystal transformation. Herein we report the first molecule, a mononuclear cobalt(ii) complex, that exhibits on-off switching between SCO and SMM reversibly during crystal-to-crystal transformation. Subtle structural transformation triggered by a simple dehydration-rehydration process induces significant geometrical changes of the CoII center and modification of the supramolecular interactions and switches its colour and magnetic properties (dark red/SCO-on/SMM-off ↔ orange/SCO-off/SMM-on). This work suggests that modification of the weak supramolecular interactions could be very effective in achieving switchable materials involving both SCO and SMM properties.
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