Abstract We review our recent studies of photochemistry and plasmon chemistry of dimethyl disulfide, (CH 3 S) 2 , molecules adsorbed on metal surfaces using a scanning tunneling microscope (STM). The STM has been used not only for the observation of surface structures at atomic spatial resolution but also for local spectroscopies. The STM combined with optical excitation by light can be employed to investigate chemical reactions of single molecules induced by photons and localized surface plasmons. This technique allows us to gain insights into reaction mechanisms at a single molecule level. The experimental procedures to examine the chemical reactions using the STM are briefly described. The mechanism for the photodissociation reaction of (CH 3 S) 2 molecules adsorbed on metal surfaces is discussed based on both the experimental results obtained with the STM and the electronic structures calculated by density functional theory. The dissociation reaction of the (CH 3 S) 2 molecule induced by the optically excited plasmon in the STM junction between a Ag tip and metal substrate is also described. The reaction mechanism and pathway of this plasmon-induced chemical reaction are discussed by comparison with those proposed in plasmon chemistry.

中文翻译：

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金属表面光化学和等离子体化学的STM研究

摘要 我们回顾了我们最近使用扫描隧道显微镜 (STM) 对吸附在金属表面上的二甲基二硫化物 (CH 3 S) 2 分子的光化学和等离子体化学的研究。STM 不仅用于以原子空间分辨率观察表面结构，还用于局部光谱学。STM 与光的光激发相结合，可用于研究由光子和局部表面等离子体激元引起的单个分子的化学反应。这种技术使我们能够在单个分子水平上深入了解反应机制。简要描述了使用 STM 检查化学反应的实验程序。基于STM获得的实验结果和密度泛函理论计算的电子结构，讨论了吸附在金属表面上的(CH 3 S) 2 分子的光解反应机理。还描述了 (CH 3 S) 2 分子在 Ag 尖端和金属基板之间的 STM 结中由光激发等离子体引起的解离反应。通过与等离子体化学中提出的那些进行比较，讨论了这种等离子体诱导的化学反应的反应机理和途径。