Collaborative Research: Surface Coordination Chemistry: Toward Novel Functionality via Understanding Substrate Charge Transfer and Oxidation State

合作研究：表面配位化学：通过了解基底电荷转移和氧化态实现新功能

• 批准号: 1310327
• 负责人: Talat Rahman
• 金额: $ 26.8万
• 依托单位: The University of Central Florida Board of Trustees
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-15 至 2017-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1310327&HistoricalAwards=false
• 关键词: Collaborative; Research; Surface; Coordination; Chemistry

In this project, funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Prof. Talat S. Rahman of University of Central Florida and Prof. Ludwig Bartels of the University of California, Riverside, and their students will use a combination of scanning tunneling microscopy and first principles electronic structure calculations to image and understand the formation of metal coordination networks on a number of metallic surfaces. They will explore in detail electronic properties of these supported metal coordination centers to address properties such as (i) charge transfer (between molecule & substrate, metal-center & molecule, and metal-center & substrate), and (ii) shape and energetics of molecular orbitals and their relation to conventional metal organic chemistry. Tuning of the effective oxidation state of metal-centers and of ligand HOMO-LUMO gaps by suitable choice of the substrate electronic properties will provide descriptors for variation of the local chemical and geometrical environment. Furthermore, general rules that define the coordination geometry around metal-centers on surfaces will be sought and conditions for stability of coordination centers with specific geometry (e.g., triagonal vs. square) will be tested. Attention will also be paid to understanding the magnetic characteristics of metal coordination centers: metal-center/molecule/substrate combinations which conspire to produce stable magnetic networks will be pursued.This project will provide state of the art modeling and/or laboratory experiences for graduate and undergraduate students and junior scientists who will be learning the techniques of chemical synthesis, formation of metal coordination networks on various metallic surfaces, imaging, and complementary ab initio electronic structure calculations. The project consists of a systematic exploration of coordination chemistry at metal surfaces which will provide the framework for establishing the rules that distinguish it from conventional ligand field and crystal field theory, which govern solution-phase metal organic chemistry. Examination of vibrational and magnetic characteristics of the systems and the special role of dispersion forces will add further value to the proposed work. Through leadership by a theorist, this project is certain to create systematic understanding, deeper insights and faster validation of findings and their generalizations to other systems. The proposed work is expected to have impact on industrial methodologies and society at large by providing access to metal coordination networks in a deterministic fashion. Control of such structures will allow continuous surface patterning from the atomic to the macroscopic scale, which should prove important for a large range of microelectronic, optoelectronic and magnetic applications. The work will also provide opportunities for educational and outreach activities with proven broad national, international and societal impact.

本研究由化学系高分子、超分子和纳米化学项目资助。中央佛罗里达大学的Rahman和滨江的加州大学的Ludwig Bartels教授及其学生将结合使用扫描隧道显微镜和第一原理电子结构计算来成像和理解许多金属表面上金属配位网络的形成。他们将详细探索这些支持的金属配位中心的电子性质，以解决诸如（i）电荷转移（分子基质，金属中心分子和金属中心基质之间），和（ii）分子轨道的形状和能量及其与传统金属有机化学的关系。通过适当地选择衬底的电子性质来调节金属中心和配体HOMO-LUMO间隙的有效氧化态，将提供局部化学和几何环境的变化的描述符。此外，将寻求定义表面上金属中心周围的配位几何形状的一般规则，以及具有特定几何形状（例如，三角形与正方形）进行测试。 还将注意理解金属配位中心的磁性特征：本项目将为研究生和本科生以及将学习化学合成技术的初级科学家提供最先进的建模和/或实验室经验，在各种金属表面上形成金属配位网络、成像和互补的从头计算电子结构计算。该项目包括对金属表面配位化学的系统探索，这将为建立将其与传统的配体场和晶体场理论区分开来的规则提供框架，这些规则支配着溶液相金属有机化学。对系统的振动和磁特性以及色散力的特殊作用的研究将进一步增加拟议工作的价值。通过理论家的领导，这个项目肯定会创造系统的理解，更深入的见解和更快的验证结果及其对其他系统的概括。预计拟议的工作将通过以确定性的方式提供对金属配位网络的访问，对工业方法和整个社会产生影响。这种结构的控制将允许从原子到宏观尺度的连续表面图案化，这对于大范围的微电子、光电和磁应用来说应该是重要的。这项工作还将为教育和外联活动提供机会，这些活动已证明具有广泛的国家、国际和社会影响。