Interpreting chemical enhancements of surface-enhanced Raman scattering
Interpreting chemical enhancements of surface-enhanced Raman scattering
复制标题
解释表面增强拉曼散射的化学增强
DOI：
10.1063/5.0138501
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发表时间：
2023-05
期刊：
影响因子：
--
通讯作者：
Ran Chen;L. Jensen
中科院分区：
文献类型：
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作者：
Ran Chen;L. Jensen
表面增强拉曼散射（Sers）提供了对弱拉曼散射的数量级增强。提高的灵敏度和光谱特征中传达的化学信息使Sers成为一种有价值的分析技术。大部分Sers增强来自电磁增强机制，而光谱特征的变化通常归因于化学增强机制。由于电磁机制已经得到了很好的研究，我们将给出一个概述的模型相关的化学机制，解释拉曼响应的电子跃迁或诱导的电子密度。在基于电子跃迁的第一类模型中，化学增强归因于分子跃迁的变化和新的电荷转移跃迁。第二类模型通过划分真实的空间中Sers系统的诱导电子密度，将化学增强与分子-金属界面附近的电荷流联系起来。选定的例子将被用来说明这两类模型，模型之间的连接被证明为原型Sers系统。
Surface-enhanced Raman scattering (SERS) provides orders of magnitude of enhancements to weak Raman scattering. The improved sensitivity and chemical information conveyed in the spectral signatures make SERS a valuable analysis technique. Most of SERS enhancements come from the electromagnetic enhancement mechanism, and changes in spectral signatures are usually attributed to the chemical enhancement mechanism. As the electromagnetic mechanism has been well studied, we will give an overview of models related to the chemical mechanism, which explain the Raman response in terms of electronic transitions or induced electron densities. In the first class of models based on electronic transitions, chemical enhancements are attributed to changes in transitions of the molecule and new charge transfer transitions. The second class of models relate chemical enhancements to charge flows near the molecule–metal interface by partitioning the induced electron density of the SERS system in real space. Selected examples will be given to illustrate the two classes of models, and connections between the models are demonstrated for prototypical SERS systems.