Sun Shumei, Tian Chuanshan, Shen Y Ron
Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro- and Nano-Photonic Structures, Fudan University, Shanghai 200433, China;
Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro- and Nano-Photonic Structures, Fudan University, Shanghai 200433, China; Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China; and
Proc Natl Acad Sci U S A. 2015 May 12;112(19):5883-7. doi: 10.1073/pnas.1505438112. Epub 2015 Apr 27.
Sum-frequency generation spectroscopy is surface specific only if the bulk contribution to the signal is negligible. Negligible bulk contribution is, however, not necessarily true, even for media with inversion symmetry. The inevitable challenge is to find the surface spectrum in the presence of bulk contribution, part of which has been believed to be inseparable from the surface contribution. Here, we show that, for nonpolar media, it is possible to separately deduce surface and bulk spectra from combined phase-sensitive sum-frequency vibrational spectroscopic measurements in reflection and transmission. The study of benzene interfaces is presented as an example.
只有当体相信号贡献可忽略不计时，和频振动光谱才具有表面特异性。然而，即使对于具有反演对称性的介质，体相贡献可忽略也不一定成立。不可避免的挑战是在存在体相贡献的情况下找到表面光谱，其中一部分被认为与表面贡献无法分离。在此，我们表明，对于非极性介质，可以通过反射和透射中的组合相敏和频振动光谱测量分别推导出表面光谱和体相光谱。以苯界面的研究为例进行了介绍。
