通过核心重建而未破坏Au-S键的化反转保护黄金纳米集群
1Departments of Physics and Chemistry, Nanoscience Center , University of Jyväskylä , FI-40014 Jyväskylä , Finland.
Journal of the American Chemical Society
|March 20, 2019
概括
黄金纳米集群 (AuNC) 可以通过核心旋转逆转其性,而不仅仅是金属-硫键断裂. 这种核心旋转机制具有较低的能量障碍,对于理解和设计稳定的性纳米材料至关重要.
科学领域:
- 计算化学
- 纳米材料科学
- 立体化学
背景情况:
- 黄金纳米集群 (AuNC) 具有独特的光学和催化性能.
- 对于AuNC的稳定性和应用来说,了解性逆转的机制至关重要.
- 现有的模型通常涉及金属-硫键断裂,这可能不能完全解释实验观测.
研究的目的:
- 在金纳米集群中研究一种新奇的性反转机制.
- 为了比较不同反转路径的能量障碍.
- 评估兴奋剂和大小对性稳定性的影响.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 嵌合金纳米集群的建模 (Au38(SR) 24和Au144 ((SR) 60).
- 用Pd和Ag合的Au38(SR) 24衍生物的分析.
主要成果:
- 提出了一种涉及集体黄金核心旋转的新型形反转机制.
- 与金属硫断裂 (2,5 eV) 相比,在Au38和Pd-doped Au38中计算了较低的能量障碍 (1-1.5 eV).
- 在较大的Au144 (SR) 60星团中发现了更高的反转障碍 (2.5-2.8 eV),这表明了更大的稳定性.
结论:
- 在AuNC中,基质逆转对核心大小,结构和金属成分敏感.
- 拟议的核心旋转机制提供了一个低能耗的途径,
- 对于要求高性稳定性的应用,Enantiopure Au144 ((SR) 60 集群具有前景.
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