Bulk Contributions Modulate the Sum-Frequency Generation Spectra of Water on Model Sea-Spray Aerosols
Bulk Contributions Modulate the Sum-Frequency Generation Spectra of Water on Model Sea-Spray Aerosols
复制标题
DOI：
10.1016/j.chempr.2018.04.007
复制
发表时间：
2018-07
期刊：
影响因子：
23.5
通讯作者：
S. K. Reddy;Raphael Thiraux;Bethany A. Wellen Rudd;Lu Lin;T. Adel;Tatsuya Joutsuka;F. Geiger;H. Allen;A. Morita;F. Paesani
中科院分区：
文献类型：
--
作者：
S. K. Reddy;Raphael Thiraux;Bethany A. Wellen Rudd;Lu Lin;T. Adel;Tatsuya Joutsuka;F. Geiger;H. Allen;A. Morita;F. Paesani
振动和频发生（vSFG）光谱被用来确定在一个模型海喷雾气溶胶表面的水的分子结构。测量和计算的光谱显示特定的功能作为三阶贡献的结果的vSFG响应，这些都与有限的界面电位。我们证明，理论建模能够分离的三阶贡献，从而允许严格的表面敏感，二阶分量的vSFG响应的系统分析。这项研究提供了基本的见解的界面分子组织和氢键结构的水，介导的非均匀过程的海喷雾气溶胶。我们的研究结果强调了计算机模拟在解释vSFG光谱和揭示复杂水界面的微观细节方面可以发挥的关键作用，由于混合了二阶，表面敏感和三阶体积依赖性对vSFG响应的贡献，因此很难从实验中提取。
Vibrational sum-frequency generation (vSFG) spectroscopy is used to determine the molecular structure of water at a model sea-spray aerosol surface. Both measured and calculated spectra display specific features as a result of third-order contributions to the vSFG response, and these are associated with finite interfacial electric potentials. We demonstrate that theoretical modeling enables separation of the third-order contributions, thus allowing for a systematic analysis of the strictly surface-sensitive, second-order component of the vSFG response. This study provides fundamental insights into the interfacial molecular organization and hydrogen-bonding structure of water, which mediate heterogeneous processes on sea-spray aerosols. Our results emphasize the key role that computer simulations can play in interpreting vSFG spectra and revealing microscopic details at complex aqueous interfaces, which can be difficult to extract from experiments because of the mixing of second-order, surface-sensitive, and third-order bulk-dependent contributions to the vSFG response.