Assembly And Magnetic Properties Of Zero-Dimensional Lanthanide-Based Molecular Magnets

Focusing on the popular research field of molecular magnetics and single-molecule magnets,seventeen mono-and dinuclear Lanthanide complexes by the nitrogen-containing ligands and nitronyl nitroxide radicals with Lanthanide ions have been obtained.The complexes were characterized by X-ray single crystal analysis,elemental analysis,ultraviolet spectroscopy and infrared spectroscopy.The fluorescence spectra and magnetic properties of some complexes were measured.The main content includes the following sections:1.A series of mononuclear octa-coordinated Lanthanide complexes have been synthesized by using the monodentate nitrogen-containing ligand 2-?2-pyridyl?-benzimidazole?PBM?as the main ligand,and hexafluoroacetylacetone as an auxiliary ligand.The magnetic measurements show that the single-nuclear Dy complex exhibit slow magnetic relaxation behavior of a single-molecule magnet.The effective energy barrier value of U_eff/k_B?0.816 K,the pre-factor of?₀?6.02?10^-6 s.2.Nine mononuclear deka-coordinated Lanthanide complexes have been synthesized by using the nitrogen-containing ligand 2-?2-pyridyl?-benzimidazole?PBM?as the main ligand,and nitrate as an auxiliary ligand.The Pr?4?,Sm?6?,Eu?7?,Tb?9?,Dy?10?,Ho?11?complexes exhibit the characteristic fluorescence of the corresponding Lanthanide ions.The results of magnetic properties show that the antiferromagnetic interactions between the Lanthanide ions in the complexes of Gd?8?,Tb?9?and Dy?10?.3.The mononuclear nona-coordinated Lanthanide complexes have been synthesized by using the nitrogen-containing ligand 3,6-bis?2-pyridyl?-1,2,4,5-tetrazine as the main ligand and hexafluoroacetylacetone as an auxiliary ligand.Magnetic analysis shows that the antiferromagnetic interaction of magnetic coupling.4.Two binuclear Lanthanide complexes have been synthesized by using meta-pyridyl-substituted nitronyl nitroxide radical?NIT3Py?and meta-pyridylphenyl-substituted nitronyl nitroxide radical?NIT3Ph3Py?.The magnetic results indicate that the antiferromagnetic interaction between the Lanthanide ions and the nitrogen radicals in the complex?16?.And there are Gd?III?-radical antiferromagnetic interaction and the ferromagnetic interaction between Gd?III?ions and radical ligands through pyridyl ring in the complex?17?.