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

麻省理工学院的罗伯特·西尔贝教授在理论和计算化学计划的支持下，对凝聚态分子系统中的光谱、弛豫和能量转移进行了理论研究。他正在推广多能级系统的四波混频光谱理论。这样的分析使人们能够解开微观的分子过程，否则当同时探测大量无序分子的光谱时，这些过程就会被平均出来。西尔贝的方法既考虑了波动的环境影响，也考虑了入射光引起的扰动。应用包括捕光络合物、其他多色体系和单量子纳米晶体。了解生物相关分子中能量传递的能力是许多生化应用所必需的，包括绿色催化、能量存储和受控光解。使用普通的光谱方法很难观察和控制这样的过程，因为分子是无序的，而且实验探测器本身可能会改变分子的标准性质。西尔贝设计了一种理论方法，使人们能够有效地推断单分子的性质和过程。同样的技术被认为对量子计算应用具有重要意义，因为它使人们能够直接探测量子点的状态。该奖项将在资助过程中支持两名研究生和一半博士后的教育。还支持针对高中生和教师的外展活动。

Professor Robert Silbey, of the Massachusetts Institute of Technology, is supported by the Theoretical and Computational Chemistry Program to perform theoretical studies of spectroscopy, relaxation and energy transfer in condensed-matter molecular systems. He is extending theories of four-wave mixing spectroscopy for multilevel systems. Such analyses allow one to unravel microscopic molecular processes, which are otherwise averaged out when spectra of a large number of disordered molecules are simultaneously probed. Silbey's methods account for both fluctuating environmental effects and perturbations due to the incident light. Applications include light harvesting complexes, other multichromophoric systems, and single quantum nanocrystals.The ability to understand energy transfer in biologically relevant molecules is necessary for many biochemical applications, which include green catalysis, energy storage and controlled photolysis. Observation and control of such processes are difficult using ordinary spectroscopic methods because the molecules are disordered and because the experimental probe itself may alter the standard properties of the molecules. Silbey has devised a theoretical means, which allows one to effectively deduce properties and processes in single molecules. The same techniques are thought to be of significance to quantum-computing applications as it enables a means for directly probing the state of a quantum dot. The award will support education of two graduate students and one half of a postdoctoral student during the course of the grant. Outreach activities to high school students and teachers are also supported.