保护酸盐的Au(20) 集群具有2.1 eV的大能量差距
Manzhou Zhu1, Huifeng Qian, Rongchao Jin
1Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|May 13, 2009
概括
合成的新型黄金集群,Au () 20 () SCH () 2CH () 2Ph () 16),表现出量子封闭和增强的稳定性. 这些20原子黄金星团拥有比以前研究的星团更大的光学能量差距.
科学领域:
- 纳米技术 纳米技术
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 酸盐覆盖的黄金集群由于其独特的电子和光学特性而引起人们的兴趣.
- 了解特定金大小的合成和稳定性对于其应用至关重要.
研究的目的:
- 开发一种动力控制的合成20原子黄金集群.
- 描述合成集群的组成,光学特性和稳定性.
- 为了比较Au(20)(SCH(2)CH(2)Ph)(16) 与其他黄金集群的属性.
主要方法:
- 动力控制的合成.
- 电子喷雾电离质谱仪 (ESI MS).电子喷雾电离质谱仪.
- 元素分析,X射线光电子光谱 (XPS),核磁共振 (NMR) 和热重力测量分析 (TGA).
- 光学吸收光谱学. 光学吸收光谱学.
主要成果:
- 成功合成了由硫酸盐覆盖的20原子黄金集群,其组成为Au(20)(SCH(2)CH(2)Ph)(16).
- 观测到的量子束行为具有逐步的光学吸收光谱和大约2.15 eV的光学能量差距.
- 证明了对多余的硫醇蚀刻的特殊强度,与较小的黄金集群形成鲜明对比.
结论:
- 合成的Au) 20 (SCH) 2 (CH) 2 (Ph) 16集群表现出独特的光学特性和增强的稳定性.
- 观察到的属性表明与其他黄金集群相比,潜在的结构差异.
- 需要对Au(20)(SCH(2) CH(2) Ph) ((16) 的晶体结构进行进一步的研究.
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