Hydrocarbon on Carbon: Coherent Vibrational Spectroscopy of Toluene on Graphite
Hydrocarbon on Carbon: Coherent Vibrational Spectroscopy of Toluene on Graphite
复制标题
DOI：
10.1021/jz2016796
复制
发表时间：
2012-02-02
影响因子：
5.7
通讯作者：
Geiger, Franz M.
中科院分区：
文献类型：
--
作者：
Achtyl, Jennifer L.;Buchbinder, Avram M.;Geiger, Franz M.
研究碳氢化合物在碳表面上的相互作用的能力是获得分子水平上的化学反应和物理性质的理解的一个组成部分。在这里，我们应用振动和频发生（SFG），以确定倾斜角甲苯，一种常见的有机溶剂，毫米厚的高取向热解石墨（HOPG）。的组合的时间延迟技术，这导致在非共振SFG响应的成功抑制，和一个零角度的方法示出克服宏观厚的碳样品所造成的“强光学吸收体”的问题，并产生甲苯的分子倾斜角在37度至42度的范围内从表面法线。这种方法的影响，用于确定碳界面上吸附的有机物种的取向，这是重要的能源相关的过程，进行了讨论。
The ability to study the interactions of hydrocarbons on carbon surfaces is an integral step toward gaining a molecular level understanding of the chemical reactions and physical properties occurring on them. Here, we apply vibrational sum frequency generation (SFG) to determine the tilt angle of toluene, a common organic solvent, on millimeter-thick highly oriented pyrolytic graphite (HOPG). The combination of a time-delay technique, which results in the successful suppression of the nonresonant SFG response, and a null angle method is shown to overcome the "strong optical absorber" problem posed by macroscopically thick carbon samples and yields a molecular tilt angle of toluene in the range of 37 degrees to 42 degrees from the surface normal. The implications of this approach for determining the orientation of organic species adsorbed on carbon interfaces, which are important for energy-relevant processes, are discussed.