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Ultrahigh-field 67Zn NMR reveals short-range disorder in zeolitic imidazolate framework glasses.

ABSTRACT: The structure of melt-quenched zeolitic imidazole framework (ZIF) glasses can provide insights into their glass-formation mechanism. We directly detected short-range disorder in ZIF glasses using ultrahigh-field zinc-67 solid-state nuclear magnetic resonance spectroscopy. Two distinct Zn sites characteristic of the parent crystals transformed upon melting into a single tetrahedral site with a broad distribution of structural parameters. Moreover, the ligand chemistry in ZIFs appeared to have no controlling effect on the short-range disorder, although the former affected their phase-transition behavior. These findings reveal structure-property relations and could help design metal-organic framework glasses.

SUBMITTER: Madsen RSK

PROVIDER: S-EPMC7325427 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Ultrahigh-field <sup>67</sup>Zn NMR reveals short-range disorder in zeolitic imidazolate framework glasses.

Madsen Rasmus S K RSK Qiao Ang A Sen Jishnu J Hung Ivan I Chen Kuizhi K Gan Zhehong Z Sen Sabyasachi S Yue Yuanzheng Y

Science (New York, N.Y.) 20200301 6485

The structure of melt-quenched zeolitic imidazole framework (ZIF) glasses can provide insights into their glass-formation mechanism. We directly detected short-range disorder in ZIF glasses using ultrahigh-field zinc-67 solid-state nuclear magnetic resonance spectroscopy. Two distinct Zn sites characteristic of the parent crystals transformed upon melting into a single tetrahedral site with a broad distribution of structural parameters. Moreover, the ligand chemistry in ZIFs appeared to have no ...[more]

PMID: 32217725

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