Synthesis And Properties Of Rare Earth (or Transition Metal) Organic Dicarboxylic Acid Binary Complex Single Crystals

Self-assembled combinations of rare earth and transition metal ions with multitopic ligands have attracted significant attentions.The interesting structural topologies of the heterometallic coordination polymers lead to the extensive potential applications as functional materials in many areas.When the rare earth metal complexes were formed,the limited rare earth metal ions combined with the ligands which are unlimited.In order to obtain a rare earth metal or a transition metal complex having a novel structure,we choose rare earth metals which are from lanthanide for coordination center ion combined with Pyridine-2,6-dicarboxylic acid as the first ligands,The structures of complexes were determined by the X-ray crystal diffraction.The thermogravimetric analysises were also discussed.（1）Using the hydrothermal method,by changing the ratio and pH value,a rare earth metal 2,6-pyridine dicarboxylic acid binary complex of different structure,and a transition metal copper succinic acid complex are obtained.（2）The synthesized crystal was analyzed by X single crystal diffraction to obtain crystal composition and structure,and some data such as bond length and bond angle were obtained.In addition,different coordination structures of the ligands were analyzed.（3）The thermodynamics of the synthesized Ho（2,6-dipic）₃Na₃O₁₈、Ho（2,6-dipic）₃·10H₂O、[Eu（2,6-dipic）₂·（H₂O）₃]_n were studied.The DSC curve showed that the complex had two endothermic peaks,and then combined with TG analysis.The thermal decomposition mechanism of the complex is derived,and the theoretical value is consistent with the actual value.（4）By analyzing and calculating the magnetic properties of the complexes Ho（2,6-dipic）₃Na₃O₁₈、[Nd（2,6-dipic）₂]_n·6H₂O、[Eu（2,6-dipic）₂·（H₂O）₃]_n,it is known that the product of the molar susceptibility of the single crystal and the temperature-temperature.On theχmT-T curve,at room temperature,theχmT value of the complex decreases with temperature,and theχmT value of the rare earth complex decreases.In the temperature range of 0³00 K,theχmT value changes with temperature,indicating that the rare earth ions have antiferromagnetic properties in the complex.