弱分子间相互作用对三金属链的分子异构体的影响
Rasmus D Poulsen1, Jacob Overgaard, Alexander Schulman
1Department of Chemistry, University of Aarhus, DK-8000 Aarhus, Denmark.
Journal of the American Chemical Society
|May 15, 2009
概括
在复合体中的晶体结构异构受溶剂分子和晶体包装的影响. 希什菲尔德分析揭示了影响分子排列和金属对金属结合的分子间相互作用的差异.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 线性链复合物,Co(3) (((二甲基胺) ((4) Cl(2) x nCH(2) Cl(2),根据间位溶剂含量表现出对称或不对称的结构.
- 了解控制这些结构变化的因素对于预测和控制材料特性至关重要.
研究的目的:
- 研究复合体中对称与非对称的金属链结构形成背后的原因.
- 分析分子间相互作用和晶体包装在影响分子异构的作用.
主要方法:
- 希尔什菲尔德分子间相互作用的表面分析.
- 使用100(1) K的X射线衍射数据来确定电荷密度.
- 在可变温度 (20,150,300 K) 的单晶同步X射线衍射.
主要成果:
- 通过希尔什菲尔德分析观察到对称和不对称的溶酸盐之间的分子间相互作用的显著差异,这表明了晶体包装的影响.
- 拓分析显示了原子 (Co(1) -Co(2) 和Co(2) -Co(3) 之间直接的金属-金属结合.
- 原子表现出不同的电子环境和拓电荷,其中Co(3) 显示出更多的离子相互作用和参与旋转交叉.
结论:
- 受溶剂含量影响的晶体包装效应在确定这些复合物的分子同质性方面发挥着重要作用.
- 在链中存在直接的金属-金属结合,具有不同程度的共价性和离子性质.
- 在Co(3) 中的旋转交叉过渡与特定的d-轨道占用率有关,并影响与温度相关的键长度.
相关概念视频
02:34Structural Isomerism
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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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03:02Colors and Magnetism
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02:52Stereoisomerism
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