对金属有机框架的结晶学影响
Seungkyu Lee1, Hans-Beat Bürgi2,3, Sultan A Alshmimri4
1Department of Chemistry , University of California-Berkeley ; Materials Sciences Division, Lawrence Berkeley National Laboratory; Kavli Energy NanoSciences Institute at Berkeley; and Berkeley Global Science Institute, Berkeley , California 94720 , United States.
Journal of the American Chemical Society
|June 26, 2018
概括
低温温度并不总是为多孔金属有机框架 (MOF) 提供高分辨率数据. 一些MOF的最佳数据是在较高的温度下获得的,因为客框架障碍减少了.
科学领域:
- 材料科学
- 晶体学
- 化学学
背景情况:
- 单晶X射线衍射 (SCXRD) 通常在高分辨率数据的冷温度下进行.
- 高度多孔的材料,如金属有机框架 (MOF),在不同的温度条件下可能表现出独特的行为.
研究的目的:
- 调查温度对SCXRD数据质量的影响.
- 确定低温数据收集的常用做法是否适用于MOF.
主要方法:
- 在不同温度 (100 K和290 K) 上对新的MOF (MOF-1004,MOF-1005) 和已确定的MOF (MOF-177,UiO-67) 进行了SCXRD实验.
- 在每个温度点分析衍射数据质量和结构溶液.
主要成果:
- 低温 (100K) 数据采集在MOF-1004和MOF-1005中的结构溶液的质量不足.
- 高温 (290 K) 数据收集为MOF-1004和MOF-1005提供了原子分辨率数据,使结构溶液成为可能.
- 对于MOF-177和UiO-67也观察到这种反向的温度行为.
结论:
- 在低温下出现不规则的客框架相互作用会引发不规则,阻碍在多孔MOF中采集高分辨率数据.
- 在更高的温度下减少了客体与框架的相互作用,从而改善了衍射数据的质量.
- 这些发现表明,高温数据收集可能是必要的,以获得某些高度多孔的MOF和具有无序分子的晶体的高分辨率结构.
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