电子光谱对同金属和异金属双核硬币金属氨酸复合体进行隔离
Marcel J P Schmitt1, Sebastian V Kruppa1, Simon P Walg1
1Department of Chemistry, Rheinland-Pfälzische Technische Universität (RPTU) Kaiserslautern-Landau, Erwin-Schrödinger Str. 53, 67663 Kaiserslautern, Germany. riehn@rptu.de.
Physical chemistry chemical physics : PCCP
|August 1, 2023
概括
这项研究检查了硬币金属氨酸复合体,揭示了由金属组成影响的电子过渡顺序,而不仅仅是金属-金属距离. 量子化学计算支持这些发现,突出了轨道贡献.
科学领域:
- 无机化学 无机化学 有机化学
- 计算化学计算化学
- 频谱学是一种光谱学.
背景情况:
- 了解双核硬币金属氨酸复合物的非共价结合和电子特性至关重要.
- 之前的研究往往缺乏对孤立的气相复合体及其内在电子转换的详细分析.
研究的目的:
- 为了阐明孤立的双核硬币金属氨酸复合物的非共价结合,结构性质和内在电子光谱.
- 为了研究金属组成对固定连接体框架内的电子转换的影响.
主要方法:
- 在现场合成和由质谱学支持的六个孤立的双核复合体的紫外线光解聚光谱 ([MM'(dcpm) 2]2+).
- 使用标量相对论GW-Bethe-Salpeter方程 (GW-BSE) 方法进行量子化学计算.
- 对与金属间距离和轨道贡献相关的过渡能量的分析.
主要成果:
- 观察到一个引人入胜的电子转换顺序 (从33,70038,500厘米到-1的蓝色转移):Cu2CuAuCuAgAu2AgAgAgAg.
- 量子化学计算成功地重现了这个顺序,并将电子带归因于金属中心的MC (dσ*-pσ) 过渡.
- 在实验中观察到的光谱变化对金属组成的敏感性不能仅仅由金属对金属距离的变化来解释.
结论:
- 电子过渡能量主要由nd{\text{n}+1s}/p-hybridization内的不同 (n+1) 轨道贡献来决定,而不是仅仅由金属对金属的距离来决定.
- 金属与金属的结合在激发时会加强,这与质谱学结果一致.
- 观察到的光谱和质谱序列,特别是对Ag/Au复合体,是Pauli排斥和金属结合体强度变化的相互作用造成的.
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