Metal-Linked Artificial Peptide Duplexes as Self-Assembled, Multifunctional Wires

这个无机、生物无机和有机金属化学项目的奖项支持宾夕法尼亚州立大学的Mary Elizabeth Williams教授使用金属配位来自组装人工肽双链，作为研究多重电子转移的功能氧化还原系统。具有直接连接的氧化还原位点的结构将允许弱耦合金属配合物之间主要通过电子跳跃进行多电子转移，这一机制在分子组装中很大程度上尚未被探索。双金属和三金属模型化合物的功能结构将被建立和研究电子如何通过它们移动。目标是：1)利用金属配位自组装同金属大分子；2)将这种方法扩展到模块化和异功能结构；3)测量双金属和三金属功能氧化还原体系中的电子转移。最初的工作将以同金属系统完成，并向简单的异功能结构迈进。使用可用的单体和合理的设计（即发夹和自对准链）进行简单的修改将用于构建这些组件。核磁共振和溶液x射线散射将被应用于液相均金属和异质金属的结构分析。电化学方法和时间分辨荧光光谱将用于测试和了解这些自组装结构的多电子转移中的电子传递机制和速率。学生和博士后研究人员将在分子设计和合成，使用广泛的实验方法，以及电子和能量转移理论方面接受广泛的培训。这个项目的复杂性要求研究这些问题的研究人员与系内和校园内的小组和专家以及阿贡国家实验室的研究人员建立联系。学生将通过本科生研究经验和宾夕法尼亚州立大学暑期研究机会项目招募。大四的研究生和博士后研究员将作为导师和监督年轻成员的项目，从而获得教学和监督经验，作为他们专业培训的一部分。

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports Professor Mary Elizabeth Williams at the Pennsylvania State University to use metal coordination to self-assemble artificial peptide duplexes that operate as functional redox systems for studying multiple electron transfers. Structures with directly connected redox sites would allow multi-electron transfers between weakly coupled metal complexes predominantly by electron hopping, a regime that is largely unexplored in molecular assemblies. Functional architectures with di- and trimetallic model compounds will be built and studied as to how electrons move through them. Goals are to: 1) use metal coordination to self-assemble homometallic macromolecules; 2) extend this approach to make modular and heterofunctional structures; and, 3) measure electron transfers in di- and trimetallic functional redox systems. Initial work will be done with homometallic systems and move forward with simple heterofunctional structures. Facile modifications using available monomers and rational design (i.e. hairpin and self-aligning strands) will be used in constructing these assemblies. NMR and solution x-ray scattering will be applied to obtain structural analyses of the solution-phase homometallic and heterometallic species. Electrochemical methods and time resolved fluorescence spectroscopy will be used to test and understand the mechanisms and rates of electron transport in the multi-electron transfers of these self-assembled structures. Student and postdoctoral researchers will be broadly trained in molecular design and synthesis, use of a wide range of experimental methodologies, and electron and energy transfer theory. The complexity of this project requires that researchers working on these problems make connections to groups and experts within the department and across campus, and with researchers at Argonne National Labs. Students will be recruited through the Research Experience for Undergraduates and the Penn State Summer Research Opportunities Programs. Senior graduate students and postdoctoral researchers will serve as mentors and oversee the projects of younger group members, thereby gaining teaching and supervisory experience as part of their professional training.