Relaxation, Coherence, and Optical Control of Time-Dependent Molecular Condensed-Phase Dynamics

Jeffrey Cina获得了理论和计算化学项目的资助，继续他在时间相关的凝聚相分子体系的相干性和光学控制领域的理论研究。中国寻求发展一个全面的超短脉冲传播理论，这将有助于模拟各种时间分辨非线性光学实验，并为进一步发展分子和固体的光学控制提供有用的工具。影响分子内部和分子之间电子和能量转移速率的各种类型的弛豫过程也将被研究。要研究的特定弛豫包括那些在电子基态中表现出相干变化的弛豫；在电子基态中具有较大幅度尺寸或形状变化的；以及那些涉及在经典可区分的分子内或宿主-介质构型之间的远距离叠加。拟议的工作将结合形式分析理论和计算模拟，并将涉及与几个实验组的直接合作。超短激光脉冲提供了一种强大的手段，使物质进入不寻常的状态，远离热平衡。这些状态可能具有不同寻常的化学或物质性质，与正常状态下的凝聚态截然不同。这项资助下的工作涉及理论研究，探索这些不寻常状态的性质，以及如何制备它们和如何检测它们。这项工作是在与进行相关实验研究的人员密切和直接接触的情况下进行的。通过这种方式，来自理论工作的理解在短期内被应用于实验数据的分析和解释。

Jeffrey Cina is supported by a grant from the Theoretical and Computational Chemistry Program to continue his theoretical research in the area of coherence and optical control of time-dependent condensed-phase molecular systems. Cina seeks to develop a comprehensive theory of ultrashort-pulse propagators that will facilitate the simulation of a wide variety of time-resolved nonlinear optical experiments and provide a useful tool for the further development of optical control of molecules and solids. Various types of relaxation processes that influence the rate of electron- and energy-transfer within and between molecules will also be investigated. Specific relaxations to be investigated include those exhibiting coherent changes in the electronic ground state; those featuring large-amplitude size or shape changes in the electronic ground state; and those involving long-range superpositions between classically distinguishable intra-molecular or host-medium configurations. The proposed work will use a combination of formal analytical theory and computational simulation, and will involve a direct collaboration with the several experimental groups.Ultra-short pulses of laser light provide a powerful means to place matter into unusual states, far from thermal equilibrium. These states may have unusual chemical or material properties quite different from those of condensed matter in its more normal states. The work under this grant involves theoretical studies which explore the properties of these unusual states as well as how they may be prepared and how they may be detected. The work is being carried out in close and direct contact with people who are making related experimental studies. In this way, the understanding coming from the theoretical work is being applied, in the near term, to the analysis and interpretation of experimental data.