金属-金属键长度的变化在Co ((3) ((((二甲基胺)) ((4) Cl ((2):键拉伸同质性,晶体场效应,或旋转过渡过程? 一个DFT研究
M M Rohmer1, A Strich, M Bénard
1Laboratoire de Chimie Quantique, UMR 7551, CNRS and Université Louis Pasteur, F-67000 Strasbourg, France.
Journal of the American Chemical Society
|September 13, 2001
概括
研究了复合物的结构行为. 研究发现,虽然对称的形状更稳定,但扭曲的形状更稳定.
科学领域:
- 无机化学 无机化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 在两种晶体形式中,Co ((3) (((dipyridylamide)) ((4) Cl ((2) 复合体表现出独特的结构行为.
- 研究这个三复合物的对称和非对称框架对于理解其特性至关重要.
研究的目的:
- 通过计算方法研究了Co(3)(dipyridylamide)(4)Cl(2) 的前所未有的结构行为.
- 确定复合物的不同结构形式的电子配置和稳定性.
主要方法:
- 使用梯度校正密度函数理论 (DFT) 的计算.
- 对地面状态潜在能量表面和电子配置的分析.
- 基于海森堡哈密尔顿式的现象学模型的应用.
主要成果:
- 低旋转 (双重) 配置是孤立分子最稳定的,与对称的X射线结构密切匹配.
- 三聚框架的扭曲导致双状态的轻微不稳定,但很重要.
- 非对称的结构是最低的能量四重奏状态更好地复制,这表明它在更高的温度下发挥作用.
结论:
- 两种晶体形式的Co ((3) ((dipyridylamide) ((4) Cl ((2) 不严格地被认为是键延伸同位素.
- 观察到的与温度相关的结构变异性归因于激发四重奏状态的渐进群体.
- 局部力量,而不是非局部化的西格玛结合,主要决定对称结构的稳定性.
相关概念视频
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