Ultrafast Spectroscopy and Other Applications of Lasers in Chemistry

宾夕法尼亚大学的Robin Hochstrasser教授受实验物理化学项目资助，进行液相化学动力学实验。这一建议代表了Hochstrasser教授开创的二维时间分辨红外光谱的系统发展。这些方法在微波区有类似的核磁共振，可以产生关于分子振动动力学和耦合以及液体样品本身结构的非常详细的信息。多肽的二维红外研究旨在提高我们对蛋白质结构和动力学的理解。其他多维激光实验旨在获得对液体（包括纯水和聚合物）的结构和动力学的新见解。二维红外光谱的工作非常及时地解决了对新方法的需求，为蛋白质、聚合物和液体结构的测定提供了突破。与将分子视为溶液中的离散粒子的传统思维方式不同，这项工作引入了一种新的范式——分子被视为耦合振动子的扩展网络。液体结构的精确图像为解决生物分子和环境问题提供了一些必要的关键信息。

Professor Robin Hochstrasser of the University of Pennsylvania is funded by the Experimental Physical Chemistry program to perform experiments on liquid phase chemical dynamics. This proposal represents the systematic development of two-dimensional time-resolved infrared spectroscopies, which Professor Hochstrasser has pioneered. These methods, which have analogs in the microwave region using NMR, can yield highly detailed information about molecular vibrational dynamics and coupling and the structures of the liquid samples themselves. Two dimensional IR studies on polypeptides are aimed at improving our understanding of the structure and dynamics of proteins. Other multidimensional laser experiments are aimed at gaining new insights into the structure and dynamics of liquids, including neat water, and polymers. The work on two-dimensional infrared spectroscopy is extremely timely in addressing the need for new methods to provide breakthroughs in determining protein, polymer and liquid structures. Instead of the traditional way of thinking about molecules as discrete particles in solution, this work introduces a new paradigm -- molecules are considered as extended networks of coupled vibrators. Accurate pictures of liquid structures provide some of the key information necessary for addressing biomolecular and environmental problems.