Abstract Sum-frequency generation vibrational spectroscopy (SFG-VS) was first developed in the 1980s and it has been proven a uniquely sensitive and surface/interface selective spectroscopic probe for characterization of the structure, conformation and dynamics of molecular surfaces and interfaces. In recent years, there have been many progresses in the development of methodology and instrumentation in the SFG-VS toolbox that have significantly broadened the application to complex molecular surfaces and interfaces. In this review, after presenting a unified view on the theory and methodology focusing on the SFG-VS spectral lineshape, as well as the new opportunities in SFG-VS applications with such developments, some of the controversial issues that have been puzzling the community are discussed. The aim of this review is to present to the researchers and students interested in molecular surfaces and interfacial sciences up-to-date perspectives complementary to the existing textbooks and reviews on SFG-VS.

中文翻译：

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复杂分子表面和界面的和频生成振动光谱 (SFG-VS)：光谱线形测量和分析以及一些有争议的问题

摘要 和频发生振动光谱 (SFG-VS) 于 1980 年代首次开发，已被证明是一种独特的灵敏和表面/界面选择性光谱探针，用于表征分子表面和界面的结构、构象和动力学。近年来，SFG-VS 工具箱中的方法学和仪器开发取得了许多进展，显着扩大了对复杂分子表面和界面的应用。在这篇综述中，在对聚焦于 SFG-VS 谱线形的理论和方法论提出统一观点后，以及随着此类发展的 SFG-VS 应用的新机遇，一些一直困扰社区的有争议的问题是讨论。