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Synthesis and Characterization of Amphiphilic Gold Nanoparticles
Published on: July 2, 2019
从黄金中的素光还原性消除 (III) 中心
Thomas S Teets1, Daniel G Nocera
1Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA.
Journal of the American Chemical Society
|May 9, 2009
概括
黄金 (III) 复合物在LMCT激发时经历轻松的素 (X2) 光淘汰. 这项研究表明,从单体和双金属黄金中心分别进行了前所未有的两电子和四电子素光去除.
科学领域:
- 无机化学 无机化学
- 摄影化学的使用.
- 有机金属化学 有机金属化学
背景情况:
- 众所周知,黄金 (III) 复合物经历了合物到金属电荷转移 (LMCT) 激发.
- 从过渡金属中心中消除素是各种化学过程中的关键反应.
研究的目的:
- 为了研究从单合金和双合金金 (III) 复合物中素 (X2) 的光去除.
- 在LMCT激发时探索M-X键激活和素消除的机制.
- 描述前所未有的多电子光淘汰路径.
主要方法:
- 单体Au2 (III) (PR3) X3和双金属Au2 (I,III) (μ-CH2 (R2P)) X4 / Au2 (III,III) (μ-CH2 (R2P)) X6复合物的合成.
- 光化学实验涉及LMCT激发溶液中的黄金复合物.
- 使用量子产量测量和在没有/存在化学陷的情况下,分析素光生成.
主要成果:
- 对单体和双金属黄金复合体都观察到轻松的素 (X2) 光淘汰.
- 从单体中心实现了前所未有的X2的两电子光去除和从双金属中心实现了四电子光去除.
- 对于X2光生成的量子产量始终在10%到20%之间,对连接体或核度的依赖最小.
- 证明了有效的,没有陷的素消除,这是过渡金属中心的罕见现象.
结论:
- 黄金的LMCT光化学 (III) 复合物使素具有新的多电子光去除途径.
- 观察到的高效且无陷的素消除为合成应用提供了新的可能性.
- 这项工作扩大了对有机金属黄金化学中的光化学反应性的理解.
相关概念视频
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