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

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.

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p. 1473-1476
American Association for the Advancement of Science (AAAS)
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National Science Foundation
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