测定Au21 ((S-Adm) 15的总结构和化黄金纳米集群的几何/电子结构演变
Shuang Chen1, Lin Xiong2, Shuxin Wang1
1Department of Chemistry and Center for Atomic Engineering of Advanced Materials, Anhui University , Hefei, Anhui 230601, People's Republic of China.
Journal of the American Chemical Society
|August 24, 2016
概括
这项研究揭示了超小的金纳米集团如何改变它们的原子包装结构. 一个新的黄金纳米集群,Au21(S-Adm) 15,从Au18(SR) 14中生长,显示了从六角密封到面中心立方体的转变.
科学领域:
- 材料科学
- 纳米技术
- 化学学
背景情况:
- 较大的黄金纳米粒子通常表现出面中心立方体 (fcc) 原子包装.
- 超小的金纳米集群表现出不同的原子包装结构 (fcc,六角密封包装 (hcp),以身体为中心的立方体 (bcc)) 受到连接体保护的影响.
- 黄金纳米集群中的这些包装结构之间的转换机制在很大程度上仍未被探索.
研究的目的:
- 研究超小金纳米集团的生长机制和结构转变.
- 为了阐明面中心立方体 (fcc) 结构形成在酸盐保护的金纳米集群的起源.
- 报告一种新的黄金纳米集群的合成和结构特征,Au21(S-Adm) 15.
主要方法:
- 新纳米团的总结构确定X射线晶体学.
- 从前体 Au18(SR) 14 中合成 Au21(S-Adm) 15.
- 密度函数理论 (DFT) 计算以了解增长机制和电子结构.
主要成果:
- 一个新的金纳米集群,Au21(S-Adm) 15,已成功合成和表征.
- 结构分析显示,Au18中的六角密封 (hcp) Au9核转化为Au21中的面中心立方 (fcc) Au10核.
- 密度函数理论 (DFT) 的计算为推动这种结构转换的几何和电子因素提供了洞察力.
结论:
- 这项研究展示了超小金纳米集中的原子包装转换的具体实例.
- 这些发现提供了关于生长机制和导致酸盐保护黄金纳米集群中面中心立方体 (fcc) 结构形成的关键信息.
- 这项研究有助于理解配体保护的黄金纳米集群中的结构性质关系.
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