δ-结合调节形式双价的稀土烯复合物的电子结构
Ross E MacKenzie1,2, Tomáš Hajdu2,3, John A Seed1,2
1Centre for Radiochemistry Research, The University of Manchester Oxford Road Manchester M13 9PL UK.
Chemical science
|September 2, 2024
概括
新的双价稀土 (RE) 复合体揭示了独特的结合. 具有非Aufbau配置的复合体显示金属结,与具有局部4f电子的复合体不同,突出通过连接体设计可控制的细微特性.
科学领域:
- 无机化学 无机化学 有机化学
- 有机金属化学 有机金属化学
- 稀土化学 稀土化学
背景情况:
- 最近的进展使得与非Aufbau电子配置的双价稀土 (RE) 复合物的隔离成为可能.
- 这些配置提供了独特的粘合图案和磁性特性.
研究的目的:
- 为了合成和表征一系列稀土的双价双结合的烯复合物.
- 研究这些复合体的电子结构和粘合特性.
- 为了探索电子配置对金属-体相互作用的影响.
主要方法:
- 合成双价比 bis-tethered 烯复合物 [RE(NHAriPr ) 2 .
- 液体溶液电子偏磁共振 (EPR) 光谱学.
- 密度函数理论 (DFT) 的计算.
- 紫外-对-红外光谱学. 紫外-对-红外光谱学.
主要成果:
- EPR光谱学证实了Sc,Y和La复合体 (2Sc,2Y,2La) 的正式nd1配置.
- 计算揭示了通过将nd价值电子混合到arene π*轨道中的nd1复合体中的金属-烯 δ-结合.
- 2Y复合体的结构修改显著改变了金属d轨道对SOMO的贡献.
- 具有4fn配置 (2Sm, 2Eu, 2Tm, 2Yb) 的复合体显示出高度局部化的f电子与微不足道的金属结合.
结论:
- 双重的稀土烯复合体表现出根据它们的电子配置 (nd1 vs. 4fn) 的细微物理化学特性.
- 在nd1复合体中,金属-烯结合是显著的,但在4fn复合体中却不存在.
- 连接物修饰提供了一条控制这些特性的途径.
- 结合实验和理论方法的综合方法对于理解这些系统至关重要.
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