Theoretical Investigations of the Spectroscopy and the Associated Structure and Dynamics of Liquids and Their Interfaces

南佛罗里达大学的Brian Space教授得到了理论和计算化学计划的支持，从理论上研究光谱与液体及其界面的相关结构和动力学之间的相关性。这项研究将通过了解分子在红外光下的反应，进一步了解凝聚相的结构和动力学。特别感兴趣的是描述因存在共振和非共振激励而变得复杂的系统。了解这些新出现的光谱技术对于选择性探测特定位置的分子和在纳米尺度上操纵物质是重要的。这项工作是通过发展理论表达式和有效的计算机策略来从分子动力学模拟和瞬时简正波计算中计算液体的光谱可观测值。材料之间的界面在生物学、化学和物理学中是至关重要的，但很难可靠地表征。为此目的，已经开发了能够探测界面的新的实验光谱方法。然而，与实现界面特定光谱的承诺相关的一个主要问题是确定如何解释从实验光谱特征中收集的信息，特别是因为这些特征可能是由于溶剂和界面性质。溶剂效应的模拟特别具有挑战性，因为它需要准确描述偶极矩系统的动力学。这项研究是与强有力的本科生和研究生教育计划协调进行的。

Professor Brian Space, of the University of South Florida, is supported by the Theoretical and Computational Chemistry Program to theoretically investigate correlations between spectroscopy and the associated structure and dynamics of liquids and their interfaces. This research will further the understanding of condensed-phase structure and dynamics by understanding how molecules respond when exposed to infrared light. Particular interest is in describing systems that are complicated by the presence of both resonant and nonresonant excitations. Understanding these emerging spectroscopic techniques is of import to selective probing of site-specific molecules and to the manipulation of matter at the nanoscale. The work proceeds by development of theoretical expressions and efficient computer strategies for calculating spectroscopic observables for liquids from molecular dynamical simulations and instantaneous normal mode calculations. Interfaces between materials are critically important in biology, chemistry, and physics but are difficult to reliably characterize. New experimental spectroscopic approaches capable of probing the interfaces have been developed for such purposes. However, a primary issue related to fulfilling the promise of an interface-specific spectroscopy is in determining how to interpret the information gleaned from experimental spectral signatures especially since these signatures may be due to both solvents and interfacial properties. Simulation of the solvent effects is particularly challenging since it requires the accurate description of the dynamics of a system of dipole moments. This research is performed in concert with strong undergraduate and graduate education initiatives.