尖端增强拉曼散射的第一原理模拟揭示了基板在高分辨率图像上的积极作用
Yair Litman1,2, Franco P Bonafé2, Alaa Akkoush2,3
1Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
The journal of physical chemistry letters
|July 24, 2023
概括
这项研究引入了一种用于Tip增强的拉曼散射 (TERS) 成像的新计算方法,它结合了TD-DFT和DFPT. 它揭示了化学效应显著改变了TERS图像,这对于纳米级分子运动理解至关重要.
科学领域:
- 表面科学是一门科学.
- 计算化学是一种计算化学.
- 频谱学是一种光谱学.
背景情况:
- 尖端增强拉曼散射 (TERS) 为原子运动研究提供亚纳米分辨率.
- 当前的理论TERS解释经常使用简化的局部电场近似值.
研究的目的:
- 为准确的TERS图像模拟开发一个第一原则的计算方法.
- 研究化学效应对吸附分子TERS光谱的影响.
主要方法:
- 时间依赖密度函数理论 (TD-DFT) 和密度函数扰乱理论 (DFPT) 的结合.
- 使用现实的局部电场计算拉曼截面.
- 在,C60和Ag100上模拟的TERS和TCNE).
主要成果:
- 开发了一种基于第一原则的新TERS模拟方法.
- 证明了对吸附分子的化学作用会显著改变TERS图像.
- 展示了在TERS模拟中包括化学相互作用的重要性.
结论:
- 精确的TERS模拟需要将吸附分子的化学效应纳入.
- 这种方法可以在纳米级分子研究中进行更好的理论-实验比较.
- 通过改进的TERS解释,提高了对纳米级分子运动的理解.
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