通过光学吸收光谱和理论计算澄清阴离子模拟银纳米集群的电子结构
Yusuke Horita1, Sakiat Hossain2, Mai Ishimi1
1Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
Journal of the American Chemical Society
|October 20, 2023
概括
离子模拟的银纳米集群 (Ag NC) 具有独特的电子结构,与无模拟的Ag NC不同. 它们的光学吸收特性来自于特定的电荷转换和轨道合,与超原子模型不同.
科学领域:
- 无机化学
- 材料科学
- 纳米技术
背景情况:
- 离子模板银纳米集群 (Ag NC) 的电子结构比传统的无模板Ag NC了解得更少.
- 了解这些结构对于开发具有定制性质的新型纳米材料至关重要.
研究的目的:
- 合成和表征新的阴离子模板AgNCs.
- 研究和阐明这些新型AgNC的独特电子结构和光学特性.
- 将它们的电子结构与无模板的AgNC和超原子概念进行比较.
主要方法:
- 三个新的离子模板AgNC的合成:S@Ag17(S-4CBM) 15 ((PPh3) 5),S@Ag18 ((S-4CBM) 16 ((PPh3) 8),和Cl@Ag18 ((S-4CBM) 16 ((PPh3) 8).
- 单晶X射线晶体学以确定核心结构 (S@Ag6,S@Ag10,Cl@Ag10).
- 用光学光谱和理论计算来研究电子结构.
主要成果:
- 合成的AgNC具有不同的S@Ag6,S@Ag10和Cl@Ag10核.
- 电子结构不同于无模板的AgNC,不符合超原子概念.
- 在S2-模板的AgNC中,光学吸收 (550-400 nm) 是由于从Ag-轨道向S2-部分的电荷过渡.
- Cl-模板的AgNC存在于中性分子,而不是离子对,单联单独占据的轨道有助于光学吸收.
结论:
- 阴离子模板显著改变了AgNC的电子结构.
- 这些发现挑战了这些特定纳米集群的超原子概念等现有模型.
- 这项研究提供了关于阴离子模板AgNC的结构属性关系的新见解.
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