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Reversible on-off switching of both spin crossover and single-molecule magnet behaviours via a crystal-to-crystal transformation.

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 Co^II 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.

SUBMITTER: Shao D

PROVIDER: S-EPMC6202758 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Reversible on-off switching of both spin crossover and single-molecule magnet behaviours <i>via</i> a crystal-to-crystal transformation.

Shao Dong D Shi Le L Yin Lei L Wang Bao-Lin BL Wang Zhen-Xing ZX Zhang Yi-Quan YQ Wang Xin-Yi XY

Chemical science 20180827 41

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 Co<sup>II</sup ...[more]

PMID: 30450182

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