Syntheses,Structures And Properties Of Alkaline-earth Coordination Polymers

The Metal-Organic Frameworks (MOFs) are comprised of infinite networks ofmetal centers or inorganic clusters bridged by simple organic linkers throughmetal ligand coordination bonds. The SCCs encompass discrete systems in whichcarefully selected metal centers undergo self-assembly with ligands containingmultiple binding sites oriented with specific angularity to generate a finitesupramolecular complex. On the most basic level, both SCCs and MOFs share thedesign of metal nodes linked by organic ligands and such constructs can be broadlydefined as metal organic materials (MOMs)According to the principles of crystal engineering, we select three kinds of rigidaromatic carboxylate ligand as organic ligands with alkaline-earth metal ion andtransition metal ion to successfully synthesize five novel Alkaline-earth andheterometallic metal coordination polymers by reasonable design and syntheticpathways under hydrothermal conditions. These compounds possess specialstructures and properties.In chapter one, we first briefly describes the history of research and developmentprocess of metal organic materials (MOMs); second，we expound the synthesis andcharacterization methods of MOFs; thirdly characteristics and application status ofalkaline earth metal coordination compounds were stated; finally the purpose, significance and major research results of our works have been introduced. We alsohave introduced the part of experimental reagents and characterization of testmethods used in this paper.The second chapter on the basis of literature, we choose rigid pluridentatev-shaped ligand isophthalic acid (m-BDC) organic ligand and alkaline earth metal(Ba)-transition metal zinc (Zn) to produce the compound [BaZn (data)2(DMF)2](1) under hydrothermal condition. In the structure of compound1, m-BDC displaytwo kinds of coordination modes (μ5-η1:η1:η1:η2and a μ5-η1:η1:η1:η3) to link the[Ba2Zn2O16] SBU forming a (8,8)-connected network. The fluorescence propertiesand thermal stabilities of1are also investigated.In chapter three, we report two coordination polymers, namely[Ca(NDC)2(DMF)2](2),[CaZn(NDC)2(DMF)2](3), based on1,4-naphthaleneacid (1,4-NDC)and alkaline-earth metal Ca/Ca-Zn. They exhibit novelthree-dimensional supermolecular structure. Compound2contains square channelfilled with coordinated DMF molecules and naphthalene ring of ligands. The ringvertically stacks with channel wall. Compound3displays the different frameworkdue to the introduction of the second metal ions which makes the coordination modeof ligand change. In compound3, naphthalene ring stacks with channel wall by acuteangle which gives rise to form the rhombus channels with the size of being8.538*8.538. In addition, the IR spectra, fluorescence properties and thermalstabilities for2and3are also investigated. It is noted that2and3offer manyadvantages as a luminescent material due to their good luminescence properties.In the fourth chapter, we successfully synthesized two new alkaline-earth metalcoordination polymers,[Ca4(PMA)2(DMF)2(H2O)6](4) and [Ba2(PMA)H2O（]5）. Inthe structure of compound4, Ca (II) centers can be connected through the carboxylthePMA ligandoms of PMA ligand to form a left-handed and a right-handed1D metalchain. All of these1D zigzag chains are connected together with the PMA ligands togive rise to2D wave layer structure. In the structure of compound5, Ba(II) has twocoordination modes and bridges with the carboxyl oxygen of the PMA ligands to form the2D layer which can be further connected by PMA ligands to extend into a3Dframework with (4,8)-connected topology.