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Volume 11 Issue 2, February 2019

The flexible facets of MOFs

The ability of some crystalline porous coordination polymers (PCP) to undergo guest-induced reversible structural changes is of great interest for practical applications such as guest separation and storage. Now, using liquid-phase atomic force microscopy, a team led by Nobuhiko Hosono and Susumu Kitagawa has imaged structural transformations occurring at the crystal–solvent interface of a PCP. The surface (illustrated on the cover) was shown to be more flexible than anticipated. It undergoes a sharp, reversible transition between tetragonal and rhombic lattices in the absence and presence of biphenyl guest molecules — even at guest concentrations that are too low to trigger structural transformations of the bulk crystal.

See Hosono et al

Image: Images are produced by Nobuhiko Hosono (Kyoto University) and Demin Liu (MolGraphics). Cover Design: Tulsi Voralia.


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News & Views

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  • Some porous coordination polymers (PCPs) are known to be flexible and guest-responsive. Now, the guest-induced sharp, reversible structural transformation of the surface of a single-crystalline PCP has been visualized by in situ liquid-phase atomic force microscopy. This local response occurred at a guest concentration that was too low to trigger changes to the bulk crystal.

    • Nobuhiko Hosono
    • Aya Terashima
    • Susumu Kitagawa
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    • Lin Liu
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    • Zhi-Tao He
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Amendments & Corrections

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In Your Element

  • Lanthanum is the first lanthanide — or the last. Or it’s not a lanthanide at all. In any case, Brett Thornton and Shawn Burdette are sure that it’s an element that might or might not be in group three of the periodic table.

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