金属有机框架玻璃中的链接器的动力
Alexander E Khudozhitkov1, Naoki Ogiwara2,3, Masaki Donoshita2,4
1Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk 630090, Russia.
Journal of the American Chemical Society
|May 2, 2024
概括
ZIF-62金属有机框架 (MOF) 玻璃的玻璃化影响了链接器的动态. 虽然快速的运动仍然存在,但玻璃化促进了较慢的协同运动,减少了激活障碍并保持了多孔性.
科学领域:
- 材料科学
- 固态化学
- 光谱学
背景情况:
- 金属有机框架 (MOF) 玻璃是一种新型混合材料,其微观动态不清楚.
- 了解MOF眼镜中的连接器移动性对于其应用至关重要.
- 之前的研究集中在宏观的质行为上,
研究的目的:
- 调查玻璃化对ZIF-62中链接器动态的影响.
- 为了阐明ZIF-62眼镜中的链接器的微观移动性.
- 为了比较晶体和玻璃ZIF-62中的链接器动态.
主要方法:
- 使用固态2H核磁共振 (NMR) 光谱.
- 使用NMR放松分析来探测链接器的移动性.
- 使用分子动力学模拟进行验证.
主要成果:
- 2H NMR显示了ZIF-62链接器的局部受限图解和大幅度扭曲.
- 玻璃化并没有显著改变快速,单独的链接器翻转动作.
- 玻璃化通过降低激活屏障,促进了缓慢的合作扭转运动.
结论:
- 玻璃ZIF-62保持永久的多孔性,与之前的发现一致.
- 由于眼镜中的协调角度扭曲, 造成了连带对齐的短距离障碍.
- 微观动态,特别是链接器的移动性,受到玻璃化过程的重大影响.
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