Theoretical Studies of Energy Transfer, Relaxation and Spectroscopy in Condensed Phase Molecular Systems

罗伯特·西尔贝提交了一份更新建议，继续他对玻璃和液体中生色团随时间变化的光谱的理论研究。这项研究将在光子回波、烧孔和超快泵浦-探测研究等实验中探索单分子光谱与分子分布光谱之间的联系。各种分子过程是由发色团与凝聚相的模式相互作用引起的，并在光谱中得到证实。将探索的具体主题是激子和激发能量转移、光谱扩散和由光谱扩散引起的能量转移。所有这些工作都将与感兴趣的实验小组合作进行。对嵌入玻璃和液体中的分子的激光光谱研究使人们能够更好地理解凝聚相系统中的相互作用和驰豫过程，包括与生物相关的光合作用反应中心和蛋白质。在大多数研究中，许多分子同时被监测，因此它们的平均行为被测量。现在，测量单个分子的方法正在发展，人们可以测量线条的形状，并实时观察分子的扩散。西尔贝正在开发新的理论解释，将单分子的实验结果与分子分布的研究联系起来。这项工作所产生的见解将在实验和理论上更好地评价凝聚相系统中的化学动力学。

Robert Silbey has submitted a renewal proposal to continue his theoretical studies of the time dependent spectroscopy of chromophores in glasses and liquids. This research will explore the connection between single molecule spectroscopy and the spectrum of distributions of molecules in experiments such as photon echo, hole burning, and ultrafast pump-probe studies. Various molecular processes that are caused by the interaction of the chromophores with modes of the condensed phase and evidenced in the spectrum will be examined. Specific topics that will be explored are exciton and excitation energy transfer, spectral diffusion, and energy transfer induced spectral diffusion. All of this work will be carried out in collaboration with interested experimental groups. Laser spectroscopic studies of molecules embedded in glasses and liquids have enabled improved understanding of interactions and relaxation processes in condensed phase systems including biologically relevant photosynthetic reaction centers and proteins. In most studies, many molecules are monitored at once, so their averaged behavior is measured. Now methods are evolving that permit measurements on a single molecule where one can measure line shapes and watch the molecule diffuse in real time. Silbey is developing new theoretical interpretations that connect experimental results on single molecules with the studies on distributions of molecules. The insights resulting from this effort will lead to a better appreciation of chemical dynamics in condensed phase systems, both experimentally and theoretically.