被硫酸盐保护的Au38纳米集群的奇拉性和电子结构
Olga Lopez-Acevedo1, Hironori Tsunoyama, Tatsuya Tsukuda
1Department of Physics, Nanoscience Center, University of Jyväskylä, FI-40014 Jyväskylä, Finland.
Journal of the American Chemical Society
|May 27, 2010
概括
研究人员探索了受酸盐保护的黄金的结构和特性,发现了一种性联体排列,在这些黄金纳米结构中诱导强的圆形二元化 (CD).
科学领域:
- 纳米材料科学 科学 纳米材料科学
- 计算化学计算化学
- 频谱学是一种光谱学.
背景情况:
- 硫酸盐保护的黄金集群具有独特的结构和电子特性.
- 了解结构和光学活动之间的关系对于纳米材料应用至关重要.
研究的目的:
- 为了研究Au(38)(SR)(24) 星团的结构,电子和光学特性.
- 为了阐明这些黄金纳米结构中循环二元化 (CD) 的起源.
主要方法:
- 密度函数理论 (DFT) 的计算用于R = CH(3) 和R = C(6) H(13).
- 粉末X射线晶体学用于R = C(12) H(25).
- 为了解释金芯的电子结构,采用了"圆柱体中的粒子"模型.
主要成果:
- 确定了一种低能结构,Au23) @ AuSR) 2), 3), 4), 5), 6), 具有双双面核心和性连接体排列.
- 计算的粉末X射线衍射函数与实验数据相匹配.
- 由于奇拉联体层,在2.2 eV以下观察到强的圆形二元化 (CD),即使是有无奇拉联体和金属芯.
- 计算的CD光谱在数量上与谷氨保护的Au的实验数据一致 (38) (((SG) ((24).
结论:
- 这项研究揭示了一种新的机制,用于强烈的性反应在酸盐保护的黄金中.
- 在金属核心上状接体的状排列可以诱导显著的光学活动.
- 这一发现对设计具有可调节光学特性的奇拉纳米材料有影响.
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