CAREER:Correlated Exciton Fluctuations in Natural and Artificial Light Harvesting Antennae

在这个由化学系化学结构、动力学和机制项目支持的项目中，北卡罗来纳大学教堂山分校的安德鲁·莫兰教授和他的研究小组将研究大型分子组合如何吸收光，并将能量从一个部分转移到另一个部分。他们将特别关注空间相关核运动在光收集机制中的作用。这项研究将利用一种叫做二维光子回波光谱（2D-PES）的飞秒激光技术，在很短的时间尺度上获得原子和分子运动的信息。此外，Moran教授和他的团队将开发一种名为带内电子相干光谱（IECS）的新技术，该技术将提供有关控制能量转移过程机制的更详细信息。要研究的系统包括光收集藻胆体，这是蓝藻细菌中的蛋白质结构，以及人工菁染料聚集体，其易于控制的形状使其成为探索结构-功能关系的优秀模型。该研究项目将促进我们对光化学过程的基本理解，并对生物科学（如光合作用）和可持续能源技术产生影响。这个研究项目将成为培养本科生和研究生的沃土。实验中使用的许多光学元件都是由研究生制造的。这种实践经验代表了化学家在超快科学的先进方法中获得跨学科专业知识的独特机会。本科生将通过制备纳米结构的聚集体做出贡献，这些聚集体将使用2D-PES和IECS进行研究。作为项目种子计划的一部分，高中生将参与研究计划。例如，他们将使用计算机模拟来设计颜料复合物并模拟它们的吸收光谱。此外，Moran教授和他的团队将为北卡罗来纳大学教育学院管理的大学预科项目进行实验室演示。大学预科课程的目标是扩大学生追求数学和科学为基础的专业和职业池。

In this project supported by the Chemical Structure, Dynamics, and Mechanisms Program of the Division of Chemistry, Professor Andrew Moran and his research group at the University of North Carolina at Chapel Hill will study how large assemblies of molecules absorb light, and transfer the energy from one part of the assembly to another. They will focus specifically on the role of spatially correlated nuclear motion in light harvesting mechanisms. The study will obtain information about atomic and molecular motions on very short time scales using a femtosecond laser technique called two-dimensional photon echo spectroscopy (2D-PES). In addition, Prof. Moran and his team will develop a new technique called intraband electronic coherence spectroscopy (IECS), which will provide more detailed information about the mechanisms controlling energy transfer processes. The systems to be studied include light harvesting phycobilisomes, which are protein structures in cyanobacteria, as well as artificial cyanine dye aggregates, whose readily controlled shapes make them excellent models for exploring structure-function relationships. This research project will advance our fundamental understanding of photochemical processes, and also have implications for the biological sciences (e.g., photosynthesis) and sustainable energy technology. The research program will be fertile ground for undergraduate and graduate students. Many of the optical components used in the experiments are/will be built by graduate students. This hands-on experience represents a unique opportunity for chemists to obtain an interdisciplinary expertise in advanced methods of ultrafast science. Undergraduates will contribute by preparing the nanostructured aggregates that will be studied using 2D-PES and IECS. As part of the Project Seed Program, high school students will participate in the research program. For example, they will use computer simulations to design pigment complexes and simulate their absorption spectra. In addition, Prof. Moran and his team will conduct laboratory demonstrations for a Pre-College program administered by the School of Education at the University of North Carolina. The goal of the Pre-College program is to broaden the pool of students pursuing mathematics and science based majors and careers.