Studies of Molecular Triplet States

在这个实验物理化学项目中，莱斯大学的R. Bruce Weisman将使用激光泵浦探测技术来研究分子的三重态激发态经历振动能量松弛和再分配、电子能量转移和反应的速率。要研究的系统包括三重态吡嗪和甲基吡嗪，使用稀有气体，CO，甲烷，乙烷，水和苯作为松弛剂。这些弛豫剂跨越了质量、极化率和极性的范围，并将提供信息，帮助阐明三重态和基态弛豫之间的机制差异。进一步的研究包括富勒烯在各种溶剂和水胶束中的三重态衰变机制和动力学。富勒烯已被证明可以产生三重态准分子，这些研究将确定准分子形成的平衡常数及其随溶剂和温度的变化。由于它们的电子自旋不成对，三重态分子通常表现出与基态完全不同的反应速率和弛豫速率。Weisman教授的研究将增强我们对这些重要化学差异的理解，并将阐明涉及准分子形成和振动能量再分配和弛豫的机制。

In this project in the Experimental Physical Chemistry Program, R. Bruce Weisman of Rice University will use laser pump-probe techniques to investigate the rates at which triplet excited states of molecules undergo vibrational energy relaxation and redistribution, electronic energy transfer, and reaction. Systems to be studied include triplet pyrazine and methylpyrazine using the rare gases, CO, methane, ethane, water, and benzene as relaxers. These relaxers span a range of mass, polarizability, and polarity, and will provide information to help clarify mechanistic differences between triplet and ground state relaxation. Further studies include the triplet decay mechanisms and kinetics of fullerenes in various solvents and in aqueous micelles. The fullerenes have been shown to produce triplet excimers, and these studies will determine the equilibrium constant for excimer formation and its variation with solvent and temperature. Due to their unpaired electron spins, triplet state molecules often exhibit rates of reaction and relaxation which are entirely different from those of the ground electronic state. Professor Weisman's studies will enhance our understanding of these important chemical differences and will clarify the mechanisms involved in excimer formation and vibrational energy redistribution and relaxation.