一个"中间旋转"的化复合物,源于非局部化的Ni2 ((μ-H) 2结合
Shu A Yao1, Amanda R Corcos, Ivan Infante
1Department of Chemistry, University of Wisconsin, Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|September 11, 2014
概括
化复合体表现出异常短的-键和意想不到的三重基态. 这种不寻常的电子配置源于特定的-Pi星轨道的半占用.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 计算化学的计算化学
背景情况:
- 化复合物在催化和协调化学中很重要.
- 了解金属对金属的结合和电子状态对于预测反应性至关重要.
研究的目的:
- 研究化复合物的结构和电子特性[Cp'Ni(μ-H) ]2.
- 为了阐明其不寻常的磁性行为的起源.
主要方法:
- 进行X射线晶体学以确定Ni-Ni键距离.
- 测量可变温度和磁场对磁场的敏感性.
- 密度函数理论 (DFT) 和完整的活性空间自相一致的场/二次扰动理论 (CASSCF/CASPT2) 的计算.
主要成果:
- 观察到一个非常短的Ni-Ni键距离为2.28638(3) Å.
- 综合体显示出一个意想不到的三重接地状态,具有90K的大零场分裂.
- 电子结构计算证实三重基态是由于半占用的退化Ni-Ni π*轨道.
结论:
- 短的Ni-Ni键和三重基态是内在联系在一起的.
- 电子结构为观测到的磁性质提供了明确的解释.
- 这项研究为迪尼克尔复合体中的结合提供了新的见解.
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