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Coordination modulated on-off switching of flexibility in a metal-organic framework.

ABSTRACT: Stimuli-responsive metal-organic frameworks (MOFs) exhibit dynamic, and typically reversible, structural changes upon exposure to external stimuli. This process often induces drastic changes in their adsorption properties. Herein, we present a stimuli-responsive MOF, 1·[CuCl], that shows temperature dependent switching from a rigid to flexible phase. This conversion is associated with a dramatic reversible change in the gas adsorption properties, from Type-I to S-shaped isotherms. The structural transition is facilitated by a novel mechanism that involves both a change in coordination number (3 to 2) and geometry (trigonal planar to linear) of the post-synthetically added Cu(i) ion. This process serves to 'unlock' the framework rigidity imposed by metal chelation of the bis-pyrazolyl groups and realises the intrinsic flexibility of the organic link.

SUBMITTER: Albalad J

PROVIDER: S-EPMC8597854 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Coordination modulated on-off switching of flexibility in a metal-organic framework.

Albalad Jorge J Peralta Ricardo A RA Huxley Michael T MT Tsoukatos Steven S Shi Zhaolin Z Zhang Yue-Biao YB Evans Jack D JD Sumby Christopher J CJ Doonan Christian J CJ

Chemical science 20211014 44

Stimuli-responsive metal-organic frameworks (MOFs) exhibit dynamic, and typically reversible, structural changes upon exposure to external stimuli. This process often induces drastic changes in their adsorption properties. Herein, we present a stimuli-responsive MOF, <b>1</b>·[CuCl], that shows temperature dependent switching from a rigid to flexible phase. This conversion is associated with a dramatic reversible change in the gas adsorption properties, from Type-I to S-shaped isotherms. The str ...[more]

PMID: 34820105

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