CAS: Highly Interacting Panchromatic Push-Pull Systems: Symmetry Breaking and Quantum Coherence in Electron Transfer

在化学系化学结构、动力学和机制A(CSDM-A)计划的支持下，北得克萨斯大学的一个研究小组正在开发一种新型的分子推挽系统，该系统能够在分子材料中实现全色光捕获和强大的分子内电荷转移，这是许多光电子学、光能采集和光学传感器应用的热门领域。这类分子体系的设计和合成将使人们能够探索电子转移中的对称性破坏、电荷转移和量子相干等光化学现象。我们将使用一系列光谱、电化学、计算和时间分辨光谱方法来研究这些体系中的超快电荷转移现象，这些光谱方法覆盖了广泛的空间和时间区域。该项目将为研究生和本科生提供广泛的教学和培训。通过参与该项目学到的技术知识、解决问题的能力和沟通技能，预计将为国家能源效率和清洁能源技术方面的科学队伍的发展做出贡献。外展工作将有助于建立一个高度多样化的研究小组，与榆树叉子教育中心合作加强普通科学教育也是该项目的一部分。通过构建由高度互动、强大的捐赠者和接受者实体组成的多模块推拉系统，北德克萨斯研究团队将解决几个科学挑战。包括：(I)开发能够在光激发下产生电荷分离态的宽带捕获分子内电荷转移络合物；(Ii)开发近红外光捕获电荷转移络合物的纳米碳(富勒烯、面体内富勒烯和单壁碳纳米管)；(Iii)探索具有四极或八极基态的多模块络合物中的氧化还原和光化学现象，如“价价电荷转移”和“对称性破坏电荷转移”，以及(Iv)观察“促进电荷转移的量子相干”过程，并在产生结构-活性关系的同时研究潜在的机理细节。这一研究项目的成果有可能对许多科学学科产生广泛影响。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Structure, Dynamics, and Mechanisms A (CSDM-A) program in the Division of Chemistry, a research team at the University of North Texas is developing a novel class of molecular push-pull systems capable of panchromatic light capture and strong intramolecular charge transfer in molecular materials highly pursued for numerous optoelectronic, light-energy harvesting, and optical sensor applications. The design and synthesis of this class of molecular systems will enable the exploration of photochemical phenomena such as symmetry-breaking charge transfer and quantum coherence in electron transfer. The ultrafast charge transfer phenomenon in these systems will be investigated using an array of spectral, electrochemical, computational, and time-resolved spectroscopic methods covering wide spatial and temporal regions. The project will provide extensive teaching and training for graduate and undergraduate students. The technical knowledge, problem-solving abilities, and communication skills learned through participating in the project are expected to contribute to the development of the nation's scientific workforce in energy efficiency and clean energy technologies. Outreach efforts will contribute to a highly diversified research group and collaboration with the Elm Fork Education Center to enhance general science education are also part of the project. By constructing multi-modular push-pull systems comprised of highly interacting, powerful donor and acceptor entities, the North Texas research team will address several scientific challenges. These include: (i) developing wide-band capturing intramolecular charge transfer complexes capable of producing charge-separated states upon photoexcitation; (ii) developing nanocarbon- (fullerene, endohedral fullerene, and single-walled carbon nanotube) derived near infrared light capturing charge transfer complexes; (iii) probing redox and photochemical phenomenon such as ‘intervalence charge transfer’ and ‘symmetry breaking charge transfer’ in multi-modular complexes having quadrupolar or octupolar ground states and (iv) observing the process of ‘quantum coherence in promoting charge transfer’ and investigating underlying mechanistic details while generating structure-activity relationships. The outcomes of this research project have the potential for broad impact across many disciplines of science.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.