双铁-二胺三核混合复合物与金属结合依赖的电子合:合成,结构和光谱表征
Cole Carter1, Yosi Kratish1, Titel Jurca1
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|October 16, 2020
概括
这项研究合成了金属二化物复合物与 bis-ferrocenyl 配体,在金属结合时揭示了铁素单元之间的电子合. 这种合影响电子转换,并允许超级交换通信,对催化有影响.
科学领域:
- 有机金属化学
- 协调化学
- 材料科学
背景情况:
- 铁衍生物是协调化学中的通用构件.
- 了解金属复合体中的电子通信对于设计功能性材料至关重要.
- 二胺 (PDI) 连接物具有可调节的电子性质.
研究的目的:
- 合成和表征一系列金属二化物复合物,其中包括双铁替代的二胺连接物.
- 通过对金属中心的协调来研究铁素单元之间的电子合.
- 探索这种电子通信对催化和材料性能的影响.
主要方法:
- 系统合成 (Fc2PDI) MCl2 复合物 (M = Mg, Zn, Fe, Co).
- 使用晶体学,光谱学 (UV-vis,近IR),电化学 (循环电压测量) 和计算方法 (DFT) 的表征.
- 电子过渡和轨道相互作用的分析.
主要成果:
- 铁素单元之间的电子合在MCl2碎片结合时被激活,由序列氧化和间电荷转移 (IVCT) 波段证明.
- 紫外线光谱显示铁素和PDI配体之间的轨道混合,过渡强度和红移增加.
- DFT计算表明通过LUMO进行超交换合,由铁素和PDI轨道之间的能量匹配介导.
结论:
- 对MCl2片段的协调诱导了Fc2PDI配体中的铁素单元之间的显著电子通信.
- 铁素氧化后的结构扭曲将空的d轨道引入二次协调球,影响电子特性.
- 这些发现对设计基于铁素金属复合物的新型催化剂和电子活性材料有影响.
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