Synthesis, Structures And Properties Of Metal-Organic Frameworks Based On Imidazolyl-Aromatic Multi-Carboxylate Acid Ligands

In recent years, metal organic frameworks (MOFs) have been widely synthesized not only for gorgeous structures, but also for lots of their potential uses, such as gas storage, ion exchange, separation, catalysis and so on. However, it is still a challenge to predict and control the final architectures of the desired crystalline products due to the structural uncertainty and diversity, since the network formation is sensitive to many factors such as organic ligands, metal ions, metal-to-ligand ratio, template, solvents, pH value, reaction temperature, and the method of crystallization, etc.Among them, organic ligands and metal ions-are the two major aspects should be considered in the construction of MOFs. As it is known, multicarboxylate ligands have been widely used to build MOFs with multi-dimensional architectures and interesting properties because of their rich and reliable coordination modes. Moreover, ligands with nitrogen donor have also shown great ability in assemble of MOFs with novel structures and natures. Taking account the facts above, we designed and synthesized a new planar-shaped dicarboxylate N-donor ligand, named 5-(1H-imidazol-l-yl)isophthalic acid (L), and further synthesized with different transition and lanthanide metal ions based on it to give complexes [PrL2(H2O)2]·H2O (1), ErL2 (2), [CoL(H2O)2]·H2O (3) and [NiL(H2O)2]·H2O (4) with diverse structures. Complex 3 and 4 is isostructure. In this thesis, we present the solvothermal synthesis, crystal structures and luminescent properties of these novel coordination polymers.