Nonlinear Raman Spectroscopy of Intermolecular Vibrations in Molecular Clusters

Felker由实验物理化学计划支持， 继续他的基态光谱研究孤立，中性 分子簇，利用质量选择性技术， 电离检测受激拉曼光谱（IDSRS）， 他的实验室。 这些研究的重点是表征分子间 中性团簇的振动能级结构，主要目标是 获得关于分子间势能的信息 表面和集体振动模式。 研究系统包括（1） 氢键二聚体，包括具有水或氨的芳族化合物，和 水二聚体，（2）较大的氢键和均相芳族 团簇;（3）自由基及其与稀有气体原子的络合物 和小分子。 该项目还包括计算工作， 模拟分子间拉曼光谱，以便于指定 观察到的谱带和分子间势参数的提取 从实验结果来看。 这项研究计划的总体目标是 为了提高关于如何收集 分子之间相互作用。 这些研究的结果预计将影响 用于凝聚相计算机建模的力场 系统，包括生物学上重要的分子，吸附的分子 用于技术应用的表面和新材料。 特别是发现水基团簇的详细性质， 可能会产生重要的影响， 环境和生物化学系统。

Felker is supported by the Experimental Physical Chemistry Program to continue his ground-state spectroscopic studies of isolated, neutral molecular clusters, using the technique of mass-selective, ionization-detected stimulated Raman spectroscopy (IDSRS) developed in his laboratory. These studies focus on characterizing the intermolecular vibrational level structures of neutral clusters, with primary goals of obtaining information pertaining to intermolecular potential energy surfaces and collective vibrational modes. Systems for study include (1) hydrogen-bonded dimers, including aromatics with water or ammonia, and water dimers, (2) larger hydrogen-bonded and homogeneous aromatic clusters, and (3) free radicals and their complexes with rare gas atoms and small molecules. The project also includes a computational effort to simulate intermolecular Raman spectra to facilitate assignment of observed bands and the extraction of intermolecular potential parameters from experimental results. The overall goal of this research program is to advance the state of knowledge pertaining to how collections of molecules interact with one another. Outcomes from these studies are expected to impact the development of force fields that are used in computer modeling of condensed phase systems, including biologically important molecules, molecules adsorbed onto surfaces and new materials for technological applications. Discovering detailed properties of water-based clusters, in particular, could have important ramifications for improved understanding of environmental and biochemical systems.