Studies of Tertiary and Quaternary Structure in Rigid Abiotic Nanoscopic Assemblies

阿灵顿德克萨斯大学的Frederick MacDonnell得到了无机化学、生物无机化学和金属有机化学计划以及纳米科学和工程倡议的支持，该计划旨在研究刚性超分子组件中的三元和四元结构。刚性树枝状大分子(先前由PI制备)将用于合成和自组装刚性的、空间定义良好的大分子组件。三菲咯啉Ru(II)类型的对映体纯络合物将作为这些组装的基本构建块。由此产生的结构将在空间上被很好地定义，因为组件在构象上是不灵活的。本项目将研究这些大分子物种的较大聚集体的‘四元结构’和行为--即‘集合体’的结构和性质。利用包括显微镜(STM和AFM)在内的多种技术，在溶液中和表面上将这些刚性的、空间定义良好的纳米复合材料作为胶体聚集体进行检测。该项目包括制备以已知的、规则的和刚性的结构排列的有机配体包围的Ru原子的小分子络合物，并以受控的方式将这些单元连接成也具有已知的、刚性的和规则的空间排列的更大的聚集体。然后，这些大分子组件将结合在一起，形成纳米级的聚集体，在溶液中，在胶体悬浮液中，作为颗粒吸附在表面上。这项工作将研究纳米级聚集体的性质和行为(物理和化学)如何与组成每个系统的组成基本单元的已知特征相关。这种多层次的方法很有可能产生理解和技术经验，这将对纳米科学和技术的进步产生相当大的好处。

Frederick MacDonnell of the University of Texas, Arlington is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program, and by the Nanoscience and Engineering Initiative, for a program of research on tertiary and quaternary structures in rigid supramolecular assemblies. Rigid dendrimers (previously prepared by the PI) will be used in synthesis and self-assembly of rigid, spatially well-defined, macromolecular assemblies. Enantiomerically pure complexes of the trisphenanthroline ruthenium(II) type will serve as the the fundamental building blocks for these assemblies. The resulting structures will be spatially well defined, since the components are conformationally inflexible. This project will examine the 'quartenary structure' and behavior of larger aggregations of these macromolecular species -- that is the structure and properties of 'assemblies of assemblies'. Those rigid, spatially well-defined nano-scale composites will be examined as colloidal aggregates in solutions and on surfaces, using several techniques, including microscopy (STM and AFM).This project involves preparing small molecular complexes containing ruthenium atoms surrounded by organic ligands arranged in a known, regular and rigid structure and linking these units, in a controlled way, into larger aggregates that also have known, rigid, and regular spatial arrangements. These macromolecular assemblies will then be combined to form nano-scale aggregates, in solution, in colloidal suspension and as particles adsorbed on surfaces. This effort will examine how the properties and behavior (both physical and chemical) of the nano-scale aggregates is related to the known characteristics of the component fundamental units that comprise each system. This multilevel approach has high probability of generating understanding and technical experience that will be of considerable benefit to the progress of nanoscience and technology.