局部秩序,混乱和中间的一切:使用Zr固态NMR光谱来探测基于的金属有机框架
Wanli Zhang1, Bryan E G Lucier1, Vinicius Martins1
1Department of Chemistry, University of Western Ontario, London, Ontario, N6A 5B7, Canada. yhuang@uwo.ca.
Physical chemistry chemical physics : PCCP
|February 12, 2025
概括
这项研究使用Zr固态NMR揭示金属有机框架 (MOF) 中的短距离结构. 这种技术精确地描述了当地环境,有助于MOF设计和理解结构与财产关系.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 核磁共振光谱学 核磁共振光谱学
背景情况:
- 在金属有机框架 (MOF) 中对金属中心进行表征对于它们的合理设计和理解结构-属性关系至关重要.
- 在Zr-MOF中阐明 (Zr) 原子周围的短距离结构可能是具有挑战性的,特别是当局乱时.
研究的目的:
- 描述七种不同的Zr-MOF中Zr原子周围的局部结构和位点对称性.
- 为了证明91Zr NMR对由客分子,链接替代和合成后修改引起的结构变异的敏感性.
- 为了利用互补的DFT计算来进行光谱解释和确定Zr协调环境.
主要方法:
- 在高磁场 (35.2 T和19.6 T) 获得静态Zr固态NMR光谱.
- 密度函数理论 (DFT) 计算的应用,以帮助光谱解释和赋值.
- 分析NMR参数以推断当地的Zr协调环境.
主要成果:
- Zr固态NMR光谱提供了有关Zr原子周围的局部结构,位点对称性和秩序的宝贵信息.
- 核磁共振光谱对MOF内部微妙的结构变化具有很高的敏感性.
- DFT计算成功地帮助分配频谱并了解NMR参数的起源.
结论:
- Zr固态NMR是一种强大的技术,用于探测Zr-MOF中的短距离结构细节,即使存在障碍.
- 结合NMR和DFT的方法可以精确地描述当地的Zr协调环境.
- 该方法适用于广泛的含材料.
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