Molecular Relaxation and Radiative Processes

Shaul Mukamel得到了理论和计算化学计划的资助，继续他在分子弛豫和辐射过程方面的研究。他将继续发展他的理论方法，研究分子聚集体中的激子动力学和振动运动，以及它们在飞秒非线性光谱中的特征。这项研究将提供一种统一的技术来解释广泛的时间分辨激光实验数据，包括泵浦-探测动力学、荧光上转换、光子回波、瞬变光栅、双折射、二向色性、时间分辨拉曼和四波混频。理论方法是基于Liouville-space格林函数技术。Mukamel将把这种方法应用于光合细菌、J聚集体和半导体纳米颗粒的捕光天线，多肽中的空穴转移，细菌视紫红质中的光异构化，以及水合电子的光子回波光谱。脉冲激光技术的出现与非线性光学技术的使用相结合，导致了大量探测气相和凝聚相分子体系的新方法。穆卡迈尔正在开发理论技术，这些技术是解释从这些实验获得的数据的核心。这些解释导致了许多关于化学反应和凝聚相体系中的溶剂化效应的重要的化学动力学见解。

Shaul Mukamel is supported by a grant from the Theoretical and Computational Chemistry Program to continue his research in molecular relaxation and radiative processes. He will continue his development of theoretical methods for investigating exciton dynamics and vibrational motions in molecular aggregates and their signatures in femtosecond nonlinear spectroscopies. This research will provide a unified technique for interpreting experimental data from a broad range of time resolved laser experiments including pump-probe dynamics, fluorescence up-conversion, photon echo, transient grating, birefringence, dichroism, time-resolved Raman, and four-wave mixing. The theoretical approach is based on Liouville-space Green's function techniques. Mukamel will apply this methodology to light harvesting antennae complexes of photosynthetic bacteria, J-aggregates and semiconductor nanoparticles, hole transfer in polypeptides, photoisomerization in Bacteriorhodopsin, and photon echo spectroscopy of the hydrated electron.The advent of pulsed laser technology combined with the use of non-linear optical techniques has led to a large number of new methods to probe gas phase and condensed phase molecular systems. Mukamel is developing theoretical techniques that are central to the interpretation of the data obtained from these experiments. These interpretations lead to many important chemical dynamical insights regarding chemical reactions and the effects of solvation in condensed phase systems.