关于蓝色转移的键的物理起源
Xiaosong Li1, Lei Liu, H Bernhard Schlegel
1Contribution from the Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
Journal of the American Chemical Society
|August 9, 2002
概括
在蓝移系统中,结可以惊人地增加结拉伸频率. 在计算研究中观察到的这种现象主要是由静电相互作用驱动的,而不是电子相关性.
科学领域:
- 计算化学计算化学
- 分子相互作用 分子相互作用
- 频谱学是一种光谱学.
背景情况:
- 键通常涉及复杂化后X-H拉伸频率的下降.
- 蓝转移的结系统显示出X-H拉伸频率的异常增加.
研究的目的:
- 为了研究负责结系统中蓝色转移现象的潜在机制.
- 确定静电相互作用与轨道相互作用在引起蓝色转移中的作用.
主要方法:
- 量子化学计算在各种理论层面上进行.
- 研究了原型的F(3) C·H··FH系统和相关分子.
- 进行了电荷再分配和分子间力量的分析.
主要成果:
- 蓝色转移在哈特里-福克水平上被重现,这表明电子相关性不是主要原因.
- 在没有碳中心或在质子捐赠者上单独对的系统中观察到大量的蓝色转移.
- 发现轨道相互作用延长了X-H键,这与蓝色转移观测相矛盾.
结论:
- 结合中的蓝色转移主要由静电相互作用控制.
- 在平衡几何学中的分子碎片之间的保利排斥压缩了X-H键,导致蓝色转移.
- 这种排斥性相互作用在这些特定系统中取代了键延长轨道效应.
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