Syntheses And Property Study Of Molecular Magnets Based On Nitronyl Nitroxide And Verdazyl Radical

Metal-radical complex is one of the most attractive fields in the molecular-based magnetic materials. Thirty-one new complexes have been designed and synthesized by using nitronyl nitroxide radical-lanthanide/transitional metal approach. The structures of eleven complexes have been determined by X-ray single crystal di diffraction technique. They have been characterized by IR, UV, AFS, TG. X-ray single crystal structure analysis. Their magnetic properties have been studied by variable-temperature magnetic susceptibility. The main work includes:1. Nine complexes have been synthesized by using3-chlorophenyl-substituted nitronyl nitroxide radical as ligand and five of them have been characterized by X-ray single crystal structure analysis, including one dual-core dimer complex [Mn2(hfac)4NITPhm-Cl)2], in which two central metal ions share two radicals; two2D plane complexes [LnⅢ(hfac)3(NIT Phm-Cl)2](Ln=ErⅢ, DyⅢ), and two1D chain complexes [LnⅢ(hfac)3(NITPhm-Cl)2](Ln=NdⅢ, TbⅢ), in which molecules are connected by hydrogen bonds.2. Using4-alloxylphenyl-substituted nitroxide radicals as ligand, eight complexes have been synthesized, and the crystal structure of [LnⅢ(hfac)3(NITPhp-OCH2CH=CH2)2](LnⅢ=GdⅢ(10), DyⅢ(11)) have been characterized by X-ray single crystal structure analysis. Complex10and11show a zig-zig chain structure and3D network structure, respectively. The Curie constant C=5.35cm3Kmol-1and Weiss constant θ=2.36K indicate ferromagnetic interaction between the spin carriers in complex10; and C=14.47cm3K mol-1,θ=-2.27K indicate antiferromagnetic interaction between the spin carriers in complex11.3. Using4-halogenophenyl-substituted nitronyl nitoxide radicals as ligand, fourteen complexes have been synthesized, and four of them have been characterized by X-ray single crystal structure analysis, including a ziro-dimentional dimer [Tb(hfac)3(NITPhp-F)2], a1D chain complex [Dy(hfac)3(NITPhp-Cl)2], a2D structure complex {[Dy(hfac)3(NITPhpBr)2]2·[Dy(hfac)3(DMF)2]} and a3D network structure complex [Tb(hfac)3(NIT Php-Br)2]. The molecules in all the complexes are connected by hydrogen bonds.In addition, the synthesis approach of verdazyl radical has been researched.