Multidimensional Femtosecond Spectroscopic Studies of Chemical Reaction Dynamics in Condensed Phases

科罗拉多大学的大卫·乔纳斯教授得到了实验物理化学项目的资助，致力于开发飞秒多维光谱方法。PI已经开发的二维电子光谱允许检查溶剂化动力学作为液体甲醇中溶剂配位的函数。本研究旨在进一步发展该方法，并将其用于研究光合反应中心和振动激发分子的双激发态。在标准的泵浦探测方法中，这些激发态吸收通常是模糊的。然后，PI建议研究光合能量和电子转移中明显长期存在的异质性。这一建议的成功成果将是适用于凝聚态动力学中许多问题的新方法。大多数实际的和工业上重要的化学反应都是在凝聚态中发生的，比如液体，但人们对溶剂如何影响反应过程知之甚少。超快动力学实验揭示了溶液中反应的一些循序渐进的细节。这些基础研究为合成化学和材料科学的许多进步奠定了基础。新的多维光谱方法的应用将揭示涉及能量转换的快速生物过程。

Professor David Jonas of the University of Colorado is funded by the Experimental Physical Chemistry program to develop femtosecond multidimensional spectroscopic methods. 2D electronic spectra developed already by the PI allows the examination of solvation dynamics as a function of solvent coordination in liquid methanol. This proposal seeks to further develop the method and use it to study the doubly excited states of the photosynthetic reaction center and vibrationally excited molecules. These excited state absorptions usually remain obscure in standard pump-probe methods. The PI then proposes to examine the apparently long-lived heterogeneity reported in photosynthetic energy and electron transfer. A successful outcome of this proposal would be new methods adaptable to many problems in condensed phase dynamics. Most practical and industrially important chemical reactions occur in condensed phases such as liquids, yet little is known how the solvent affects the course of the reactions. Ultrafast dynamics experiments reveal some of the step by step details of reactions in solution. These fundamental studies underlie many of the advances in synthetic chemistry and materials science. Applications of the new multidimensional spectroscopic methods will shed light on fast biological processes involved in energy conversion.