在六协调复合体中的Si-E (E = N,O,F) 结合:来自实验和理论电荷密度研究的新事实
Nikolaus Kocher1, Julian Henn, Boris Gostevskii
1Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Wuerzburg, Germany.
Journal of the American Chemical Society
|April 29, 2004
概括
这项研究研究了化合物的超价性,揭示了六合协调复合体中主要存在的离子键. 实验和理论分析挑战了关于的常见假设.
科学领域:
- 无机化学 无机化学 有机化学
- 计算化学的计算化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 中心原子超过八个价值电子的超价值概念仍在争论中.
- 具有高协调数 (超过四个替代物) 的化合物特别感兴趣.
- 在化学中,区分高度和高协调度是一个持续的挑战.
研究的目的:
- 用实验来确定电荷密度,并分析六合协调化合物中的结合.
- 为了研究极极的异原子键 (Si-N,Si-O,Si-F) 的性质.
- 将实验结果与理论计算进行比较,以澄清粘合特性.
主要方法:
- 实验性电荷密度的确定使用X射线衍射.
- 对电子密度进行拓分析以表征化学键.
- 气相初始计算用于理论比较.
主要成果:
- 实验性电荷密度分析显示Si-E键具有主要的离子特性.
- 对Si-E债券的共价贡献明显低于通常预期的.
- 理论计算证实了有关键极性和离子性质的实验发现.
结论:
- 这项研究提供了第一个实验证据,阐明了六合协调化合物中的结合.
- 在这种情况下,研究结果表明高度极性Si-E键的电离性比共价性更强.
- 这项工作为正在进行的关于化学中的超价值与高协调的辩论做出了贡献.
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