多模结构溶液与单片氧化物NMR结晶学
Fenghua Ding, Kent J Griffith, Can P Koçer1
1Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, U.K.
Journal of the American Chemical Society
|June 13, 2020
概括
这项研究引入了NMR结合晶体学和X射线衍射方法来解决复杂的氧化结构. 该技术精确地识别出新的基化合物中的原子排列和化学键.
科学领域:
- 固态化学
- 材料科学
- 晶体学
- 核磁共振 (NMR) 光谱学
背景情况:
- 复杂的晶体结构,特别是氧化物,在原子尺度结构确定中存在挑战.
- 准确的结构模型对于设计具有理想性质的材料至关重要,特别是用于储能应用.
- 现有的方法通常与微妙的原子细节和氧化化合物的独特特征作斗争.
研究的目的:
- 开发和应用一个结合的NMR晶体和单晶X射线衍射方法,用于复杂的氧化物的完整结构溶液.
- 为了阐明含有罕见的三角早期过渡金属氧化集群的三种新化合物的结构,
- 研究这些新型氧化集群中的化学结合和电子结构的性质.
主要方法:
- 单晶X射线衍射用于初始框架识别.
- 一维和二维固态19F核磁共振光谱,由ab initio计算支持,用于详细的结构解决方案和地点分配.
- 分子轨道理论和电子结构计算分析化学结合.
主要成果:
- K5[Mo3O4F9]·3H2O (1),K5[Mo3O4F9]·2H2O (2) 和K16[Mo3O4F9]2[TiF6]3·2H2O (3) 的完整结构溶液
- 在[Mo3O4F9]5集群中分配了九个不同的位,显示了19FNM对微妙结构变化的高度敏感性.
- 对Mo3集群的金属-金属键单元顺序和三元旋单基态 (1a21e4) 的鉴定,涉及Mo4+离子.
结论:
- 结合NMR结晶学和X射线衍射方法是解决复杂化物和氧化物结构的有效策略.
- 这种方法使我们能够详细了解先进材料的结构性质关系.
- 这项研究揭示了早期过渡金属氧化集群中的新型结合特性和电子配置.
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