通过X射线吸收光谱学揭示的交叉合催化剂的多配置电子结构
Kacie J Nelson1, Nathanael P Kazmierczak2, David A Cagan2
1Stanford PULSE Institute, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, United States.
The journal of physical chemistry letters
|December 19, 2024
概括
(II) 2,2'-双胺复合体表现出多种配置的电子结构,由X射线吸收光谱学证实. 连接体功能化影响电子性质,对于优化金属光电氧催化是至关重要的.
科学领域:
- 无机化学 无机化学
- 催化剂是一种催化剂.
- 摄影化学的使用.
背景情况:
- (II) 2,2'-双二烯复合物是金属光电氧交叉合反应中的关键中间体.
- 了解它们的电子结构对于设计改进的催化剂至关重要,但设计原则尚未确立.
研究的目的:
- 实验性地研究Ni(II) 复合物的电子结构与功能化的2.2'-二二 (bpy) 和烯联体.
- 在交叉合反应中,将连接体功能与电子性质和催化潜力相关联.
主要方法:
- 合成和表征Ni(R-bpy) ((R'-Ar) Cl复合物.
- 高分辨率的Ni K边缘和L2,3边缘X射线吸收光谱 (XAS).
- 计算研究包括多配置/多引用计算,初始和半经验方法.
主要成果:
- XAS实验提供了高度共价的Ni-aryl结合和多配置基态的证据.
- 在K边缘光谱中的前边缘特征与Ni-aryl键共价相关.
- L3边缘的光谱特征证实了金属到连接体电荷转移 (MLCT) 特性,由连接体替代物调节.
结论:
- 这些Ni(II) 复合体的电子结构确实具有多种配置,具有显著的MLCT贡献.
- 连接体设计,特别是和bpy连接体的电子推/拉效应,可以在催化周期期间调整Ni中心的电子密度.
- 这些发现为金属光电氧交叉合反应的合理催化剂设计提供了见解.
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