双金属的二分法:同轴与垂直的双金属单元在三明治化合物中的二分法
Yaoming Xie1, Henry F Schaefer Iii, R Bruce King
1Department of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, USA.
Journal of the American Chemical Society
|March 3, 2005
概括
理论研究表明,诸如可,可和可之类的二金属具有不同的金属-金属结合和结构偏好. DFT计算表明,尼基洛和铜的单元状态有利于具有垂直金属-金属键的低能结构.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学计算化学
- 无机化学 无机化学
背景情况:
- 例如 (Cp) 2M2,其中M是过渡金属的二甲,由于其独特的结合性而引起人们的兴趣.
- 之前的理论研究表明,可,可和可具有特定的结构.
研究的目的:
- 为了研究在二金属中优化结构和金属对金属的结合.
- 为了比较可,可和可的理论预测.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 进行了结构优化和债券分析.
主要成果:
- 对 (Cp) 2Zn2的理论研究预测了具有 Zn-Zn 单键 (2.33 A) 的 D5h 或 D5d 结构.
- 最初预测 (Cp) 2Ni2 (单体) 和 (Cp) 2Cu2 (三体) 具有相似的结构,分别具有Ni-Ni三重 (2.06 A) 和Cu=Cu双 (2.22 A) 键.
- 在单元状态下对 (Cp) 2Ni2和 (Cp) 2Cu2的DFT计算显示了具有垂直于Cp环轴的金属-金属键的显著较低的能量结构 (Ci对称性).
结论:
- 电子状态 (单元与三元) 显著影响二金属的优化结构.
- DFT计算预测了尼克洛和铜在单个状态中的新型低能结构.
- 这些发现强调了考虑电子配置在预测有机金属化合物的几何和结合时的重要性.
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