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Coordination modulated on-off switching of flexibility in a metal–organic framework† † Electronic supplementary information (ESI) available. CCDC 2100590–2100596. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/d1sc04712d

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. Stimuli-responsive metal–organic frameworks (MOFs) exhibit dynamic structural changes upon exposure to external stimuli. Here the coordination geometry of a post-synthetically added metal ion drastically changes the adsorption properties.

SUBMITTER: Albalad J

PROVIDER: S-EPMC8597854 | biostudies-literature |

REPOSITORIES: biostudies-literature

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