阿拉克诺 - 诺纳波兰的结构化学
Jonathan Bould1, Robert Greatrex, John D Kennedy
1School of Chemistry, University of Leeds, Leeds, UK LS2 9JT.
Journal of the American Chemical Society
|June 20, 2002
概括
结构研究表明,具有i-nonanborane几何学的化集群是一致的同结构. 这一发现支持最近对化结构和NMR化学转移的计算预测.
科学领域:
- 无机化学 无机化学
- 固态化学 固态化学
- 结构化学 结构化学
背景情况:
- 化团表现出多样化的结构和反应性.
- 阿拉克诺-i-nonanborane几何学是化化学中的一个关键结构图案.
- 了解原子的精确排列,特别是原子的精确排列,对于描述这些星团至关重要.
研究的目的:
- 阐明各种化阳离子及其添加物的详细结构.
- 为了研究arachno-i-nonanborane框架的结构一致性.
- 为了将实验结构数据与理论计算相关联.
主要方法:
- 单晶X射线衍射研究使用常规管和同步子源.
- 低温结构确定精确定位所有原子,包括.
- 实验数据与计算预测的比较 (例如,11B NMR化学转移).
主要成果:
- 确定了基本化集群的同结构性质,具有arachno-i-nonanborane几何.
- 在这些星团的开放面上确定了三个桥梁和两个内末端原子的一致排列.
- 通过新的衍射数据证实了[arachno-B(9) H(13) -4- ((NCMe) ]离子的拟议结构.
- 实验结果与结构和NMR转移的计算预测保持一致.
结论:
- 阿拉克诺-i-nonanborane框架在各种衍生品中表现出一个保存的结构图案.
- 结构性表征为化集群的理论模型提供了强有力的支持.
- 这项工作完善了我们对这些复杂无机离子中原子位置的理解.
相关概念视频
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Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
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Ozone is a symmetrical bent molecule stabilized by a resonance structure.
01:28Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
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In aldehydes (Figures 1a and 1b), the carbonyl...
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