| In 1990s,the discovery of Mn12clusters led people to build the first cognition of single-molecule magnets.The field of single-molecule magnets(SMMs)has continuously developed due to the close collaboration of scientists obtaining materials already operating above the liquid nitrogen temperature.Due to their unique properties,4f single molecule magnets have been studied deeply by researchers,involving interesting structures and multifunctional properties.Based on this hot point,the self-assembly reaction of lanthanide ions and Shciff base ligands under room temperature,afforded two series of low nuclear 4f complexes which are stable in air,12 single crystals in total.All complexes were structurally characterized by X-ray single crystal diffraction,elemental analysis and other instruments.Moreover,Magnetic and fluorescent properties are two aspects of our research.The included parts are following:1.The Schiff base ligand HL1,named((E)-2-((pyridine-2-ylmethylene)amino)phenol)),which can be gained by the condensation reaction of 2-Aminophenol and Pyridine-2-carbaldehyde,reacted with rare earth metal salts and sodium acetate as co-ligand to synthesize five isostructural binuclear lanthanide complexes[Ln2(L1)2(CH3COO)2(NO3)2(CH3OH)2](Ln=Dy(1),Gd(2))and[Ln2(L1)2(CH3COO)2(NO3)2(H2O)2]·2CH3OH(Ln=Ho(3),Tb(4),Eu(5)),respectively.And these complexes are characterized and analyzed,These five complexes are located in muffin configurations with Cssymmetry.Magnetic studies show that the imaginary part of the AC susceptibility in the complex of Dy2has obvious frequency dependence,the calculated effective energy barrier is Ueff=86.28 K and the relaxation time is?0=1.76×10-7s.2.Two salen type ligands H2L2and H2L3(H2L2=6,6'-((1Z,1'Z)-((azanediylbis(ethane-2,1-diyl))bis(azaneylylidene))bis(methaneylylidene))bis(2,4-dibromophenol),H2L3=6,6'-((1Z,1'Z)-((azanediylbis(ethane-2,1-diyl))bis(azaneylylidene))bis(methaneylylidene))bis(2-bromo-4-chlorophenol))were used to react with rare earth nitrates and dibenzoylmethane as auxiliary ligand,a series of mononuclear complexes[Ln(L2)(dbm)(H2O)](Ln=Dy(6),Tb(7),Eu(8)),[Ln(L3)(dbm)(H2O)](Ln=Dy(9),Tb(10),Eu(11))were synthesized by natural volatilization.We choosed the ligand H2L3,and auxiliary ligand sodium oxalate reacted with dysprosium trinitrate by the way of self-assembly to gain a unique trinuclear rare earth complex[Dy3(L3)3(NO3)(H2O)2(CH3OH)]·NO3·H2O(12),The structure was characterized and analyzed by X-ray single crystal diffraction.Complexes 6-11 are square antiprism configuration with D4dsymmetry.The configuration of Dy1 in the trinuclear complex is biaugmented trigonal prism,Dy2and Dy3 is in configuration of triangular dodecahedron.And magnetic data indicate that the single molecule magnet behavior disappear in complex of 6,9 and 12.Fluorescence property studies indicate complex 8 and 11 are good potential material for fluorescent devices. |
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