Metal-Organic Networks Based Upon Dicarboxylato Ligands

Network structures based upon metal-organic backbones represent a new class of functional materials that can be rationally constructed by employing the concepts of supramolecular chemistry and crystal engineering. The modularity of design strategies, the diversity of prototypal structures, and the dynamic features of networks have afforded great advantages over traditional materials syntheses. The research presented in this thesis is primarily concerned with developing an in-depth understanding of the basic principles that govern the supramolecular behaviors of metal-organic networks and gaining an experimental control over the structure and function of these new classes of hybrid materials. The use of rigid and angular organic ligands along with transition metal clusters gives rise to a wide variety of novel metal-organic architectures ranging from zero-dimensional nanostructures to three-dimensional frameworks. Conformational analysis of these structural models suggests the geometric foundations for the existence of superstructural diversity. Controlled crystallization experiments further reveal the synthetic factors that might determine the formation of supramolecular isomers. Careful selection of more labile organic components, on the other hand, leads to flexible metal-organic networks exhibiting dynamic characteristics that have not been observed in their rigid counterparts. The guest-dependent closing/opening of cavities and the ease of fine-tuning their chemical environments demonstrate the effectiveness of such a strategy in the context of generating tailored functional materials