S=N与S+-N-对比:一个实验和理论的电荷密度研究研究
1Institutes of Inorganic and Organic Chemistry, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
Journal of the American Chemical Society
|February 12, 2004
概括
这项研究通过X射线衍射和ab initio计算澄清了高价硫化合物中的结合. 结果显示,硫键是极化的S(+) -N(-),而不是经典的双键,不包括硫扩张.
科学领域:
- 无机化学 无机化学
- 计算化学的计算化学
- 量子化学 是一个量子化学.
背景情况:
- 超价硫化合物被广泛讨论,但它们的结合状况尚不清楚.
- 了解这些纽带对于推进无机和材料科学的发展至关重要.
研究的目的:
- 为了阐明高价硫物种的结合情况.
- 为了比较实验和理论的电荷密度分布和结合性质.
主要方法:
- 在四种代表性的硫化合物上进行了高分辨率低温X射线衍射实验 (T = 100 K).
- 气相初始计算用于比较分析.
- 电荷密度分布的拓分析和自然键轨道 (NBO) /自然共振理论 (NRT) 方法.
主要成果:
- 实验和理论方法同意了硫键的空间拉普拉斯分布和极化.
- 所有研究的硫键都表现出明显的两极分化,支持S(+) -N(-) 配方.
- 对于S-N债券的经典双重债券配方没有得到支持;排除了硫价值扩展.
结论:
- 超价硫物种中的结合最好用极化S(+) -N(-) 键描述,而不是经典的双键.
- 理论和实验发现始终表明明显的两极分化,并拒绝硫价值扩张.
- 这项研究提供了对各种硫化合物的结合模式的清晰理解.
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