Surface sum-frequency vibrational spectroscopy of nonpolar media
Surface sum-frequency vibrational spectroscopy of nonpolar media
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非极性介质的表面和频振动光谱
DOI：
10.1073/pnas.1505438112
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发表时间：
2015-04
影响因子：
11.1
通讯作者：
Shen Y. Ron
中科院分区：
文献类型：
--
作者：
Sun Shumei;Tian Chuanshan;Shen Y. Ron
显著性和频振动光谱（SFVS）已发展成为一种可行的表面分析工具，具有反演对称性的介质。它被认为是表面特异性的，因为在电偶极子近似下对信号的体积贡献消失。然而，人们总是担心，在电偶极子近似之外，体贡献可能是不可忽略的。如果所研究的介质没有强极性取向的表面层，则问题尤其严重。我们在这里表明，非极性介质分离良好的红外和拉曼模式，它是可能的，推导出体和表面光谱分别从组合的透射和反射相敏SFVS测量。这项工作还提供了指导方针，评估的重要性，批量贡献SFVS一般。和频发生光谱学只有在对信号的体积贡献可以忽略不计时才是表面特异性的。然而，即使对于具有反转对称性的介质，可以忽略的体积贡献也不一定是真的。不可避免的挑战是在存在体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是不可分割的。在这里，我们表明，对于非极性介质，它是可以分别推导出表面和体光谱相结合的敏感和频振动光谱测量反射和透射。苯界面的研究作为一个例子。
Significance Sum-frequency vibrational spectroscopy (SFVS) has been developed into a viable surface analytical tool for media with inversion symmetry. It is considered surface specific because the bulk contribution to the signal vanishes under the electric-dipole approximation. However, there is always the worry that beyond the electric-dipole approximation, the bulk contribution may not be negligible. The problem is particularly acute if the medium under investigation does not have a strongly polar-oriented surface layer. We show here that for nonpolar media with well-separated infrared and Raman modes, it is possible to deduce bulk and surface spectra separately from combined transmission and reflection phase-sensitive SFVS measurements. The work also provides guidelines for evaluation of the importance of bulk contribution to SFVS in general. 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.
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影响因子：
3.3
作者：
X. Wei;S. Hong;A. Lvovsky;H. Held;Y. Shen
通讯作者：
X. Wei;S. Hong;A. Lvovsky;H. Held;Y. Shen
影响因子：
2.9
作者：
B. Koopmans
通讯作者：
B. Koopmans
DOI：
10.1063/1.3586811
发表时间：
2011-05
期刊：
The Journal of chemical physics
影响因子：
--
作者：
S. Yamaguchi;K. Shiratori;A. Morita;T. Tahara
通讯作者：
S. Yamaguchi;K. Shiratori;A. Morita;T. Tahara
影响因子：
4.2
作者：
Hommel, EL;Allen, HC
通讯作者：
Allen, HC
影响因子：
--
作者：
PERSHAN, PS
通讯作者：
PERSHAN, PS