Ultrafast Dynamics and Reactivity in Ground and Excited States: Beyond the Pump-probe Method

在这项由化学部实验物理化学计划资助的项目中，Dantus将使用三脉冲、四波混频(FWM)非线性光谱学来研究NO2、CF3NO和N2O4的基态和激发态中的波包运动动力学。这项工作的目的是研究多原子体系中的分子内振动能量重新分配(IVR)和曲线交叉动力学，从而为更广泛、更广泛的研究开辟道路。这项研究要回答的具体问题是：多原子学中能量耗散和IVR的初始步骤，多维系统相空间中波包局域化的性质，以及具有高达12,000 cm-1的化学显著能量的系统中的基态动力学是什么。本项目研究的是吸收到特定分子能态的能量在一段时间内如何在整个分子中重新分配的基本问题。对这些分子内过程的深入了解可能会导致激光对化学反应的控制。这项研究是与学生和博士后研究助理进行的。他们将获得当代物理化学前沿领域的培训和知识，为进修或在工业、政府或学术界就业做准备。

In this project funded by the Experimental Physical Chemistry Program of the Chemistry Division, Dantus will use three-pulse, four-wave mixing (FWM) non-linear spectroscopy to study the dynamics of wave packet motion in the ground and excited states of NO2, CF3NO, and N2O4. The purpose of the work is to investigate intramolecular vibrational energy redistribution (IVR) and curve crossing dynamics in polyatomic systems and thereby open up the way for more general, and wider ranging investigations than done heretofore on diatomics. Specific questions to be answered in this research are about the initial steps of energy dissipation and IVR in polyatomics, what is the nature of wave packet localization in phase space for multidimensional systems, and what is the ground state dynamics in systems with chemically significant amounts of energy, up to 12,000 cm-1.This project deals with fundamental questions of how energy absorbed into specific molecular energy states redistributes itself throughout a molecule in the course of time. A good understanding of these intramolecular processes may lead to the laser control of chemical reactions. This research is undertaken with students and postdoctoral research associates. They will acquire training and knowledge in one the forefront areas of contemporary physical chemistry in preparation for advanced studies or employment in industry, government or academia.