Controlling the Rates, Distance, and Direction of Electron Transfer in Ultrafast Inorganic Ground States

控制超快无机基态中电子转移的速率、距离和方向

基本信息

批准号：
1853908
负责人：
Clifford Kubiak
金额：
$ 53万
依托单位：
University of California-San Diego
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1853908&HistoricalAwards=false
关键词：
Controlling Rates Distance Direction Electron

项目摘要

In this project, funded by the Chemical Structure, Dynamics, and Mechanisms B Program of the Chemistry Division, Professor Clifford Kubiak of the Department of Chemistry and Biochemistry at the University of California San Diego is developing new assemblies of metal complexes that undergo fast electron electron transfer (ET) reactions. These reactions are monitored by infrared spectroscopy which has picosecond (1 trillionth of a second) time resolution to follow such ultrafast reaction. The goal of these studies is to develop a fundamental understanding of the chemical factors that determine the rate, distance, and direction of ET reactions. This work may ultimately pave the way towards the design of molecular electronic devices such as switches and memory that function far faster than the current generation of computers and sensors. This project lies at the intersection between synthetic chemistry and physical characterization, providing a rich opportunity for the training of graduate and undergraduate students in cutting-edge research. Controlling the rates, distance, and direction of electron transfer broadly impacts the life sciences, technology, and energy sectors. This project represents basic research but, if successful, could ultimately benefit society in important areas including treatments for genetic disorders caused by damage to DNA; a new generation of faster, smaller, and less expensive integrated circuits; advances in artificial and natural photosynthesis and improvements in agricultural food production. Professor Kubiak involves undergraduate students in research and engages K-14 students. The group has established a new undergraduate exchange program with Cal State University Monterey Bay (CSUMB) for students to pursue research projects that can be performed partly at CSUMB and partly at UCSD during summers and school breaks. The research team also develops visualizations of complex scientific ideas and their videos are also being shared broadly with both researchers, educators and the general public. Mixed-valence dimers of triruthenium acetate clusters display rich spectroscopic evidence of ultrafast ET over long distances. They have proven to be fruitful systems in illustrating how different bridging moieties, electronic structures, and chemical environments and dynamics can impact the kinetic barriers of ET. Professor Clifford Kubiak and his group plan to develop a more complete physical chemical description of how electron transfer occurs across hydrogen bonds. They will expand the synthesis of new complexes to better understand the interplay between electron delocalization and hydrogen bonding. Additionally, they will conduct the first two-dimensional infrared spectroscopy (2D-IR) studies of intramolecular ET on the picosecond timescale. They will use synthetic studies to probe bridging ligand dynamics and its relation to ET. This research will attempt to demonstrate vibrational control of the ET coordinate to change its rate and direction. Finally, the team will design and synthesize new supramolecular assemblies that exhibit mixed valency between pendant tri-ruthenium redox centers through semiconducting metal oxide nanoparticles.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在该项目中，由化学系化学结构、动力学和机理 B 项目资助，加州大学圣地亚哥分校化学与生物化学系的 Clifford Kubiak 教授正在开发新的金属配合物组件，这些组件可经历快电子转移（ET）反应。这些反应由红外光谱仪监测，红外光谱仪具有皮秒（万亿分之一秒）的时间分辨率来跟踪这种超快反应。这些研究的目标是对决定 ET 反应的速率、距离和方向的化学因素有一个基本的了解。这项工作最终可能为分子电子设备的设计铺平道路，例如开关和存储器，其运行速度远远快于当前一代计算机和传感器。该项目位于合成化学和物理表征的交叉点，为研究生和本科生的前沿研究培训提供了丰富的机会。控制电子转移的速率、距离和方向广泛影响生命科学、技术和能源领域。该项目代表了基础研究，但如果成功，最终可能在重要领域造福社会，包括治疗由 DNA 损伤引起的遗传性疾病；新一代更快、更小、更便宜的集成电路；人工和自然光合作用的进步以及农业粮食生产的改进。库比亚克教授让本科生参与研究，并让 K-14 学生参与其中。该小组与加州州立大学蒙特利湾分校 (CSUMB) 建立了一项新的本科生交换项目，供学生进行研究项目，这些项目可以在暑假和学校放假期间部分在 CSUMB 进行，部分在 UCSD 进行。研究团队还开发了复杂科学思想的可视化，他们的视频也与研究人员、教育工作者和公众广泛分享。醋酸三钌簇的混合价二聚体显示出长距离超快蒸散的丰富光谱证据。事实证明，它们是富有成效的系统，说明了不同的桥接部分、电子结构以及化学环境和动力学如何影响 ET 的动力学势垒。克利福德·库比亚克（Clifford Kubiak）教授和他的团队计划对氢键上电子转移如何发生进行更完整的物理化学描述。他们将扩大新配合物的合成，以更好地理解电子离域和氢键之间的相互作用。此外，他们还将在皮秒时间尺度上首次对分子内 ET 进行二维红外光谱 (2D-IR) 研究。他们将利用合成研究来探讨桥连配体动力学及其与 ET 的关系。这项研究将尝试演示 ET 坐标的振动控制，以改变其速率和方向。最后，该团队将设计和合成新的超分子组件，通过半导体金属氧化物纳米颗粒在悬垂的三钌氧化还原中心之间表现出混合价态。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和更广泛的评估进行评估，被认为值得支持。影响审查标准。