Studies of Tertiary and Quaternary Structure in Rigid Abiotic Nanoscopic Assemblies

德克萨斯大学阿灵顿分校的Frederick MacDonnell得到无机、生物无机和有机化学项目以及纳米科学与工程倡议的支持，从事刚性超分子组装中三级和四级结构的研究项目。 刚性树枝状聚合物（先前由PI制备）将用于合成和自组装刚性、空间上明确定义的大分子组装体。对映体纯配合物的三菲咯啉钌（II）型将作为这些组件的基本构件。所得的结构将在空间上良好地限定，因为组分在构象上是不可弯曲的。这个项目将研究这些大分子物种的“四元结构”和更大聚集体的行为-即“组装体”的结构和性质。这些刚性的，空间上明确界定的纳米级复合材料将作为胶体聚集体在溶液中和表面上进行检查，使用几种技术，包括显微镜（STM和AFM）。该项目涉及制备含有钌原子的小分子络合物，所述钌原子被以已知的、规则的和刚性的结构排列的有机配体包围，并且以受控的方式将这些单元连接成更大的聚集体，严格而规则的空间布局。然后，这些大分子组装体将在溶液中、胶体悬浮液中以及作为吸附在表面上的颗粒结合以形成纳米级聚集体。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件基本单元的已知特性相关。这种多层次的方法有很高的概率产生的理解和技术经验，将是相当有益的纳米科学和技术的进步。

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.