| In this paper,by selecting 2,3-pyrazinedicarboxylic acid?2,3-H2pzdc?as ligand,by self-assembling of 2,3-pzdc,different lanthanide ions,and different transition metal ions under hydrothermal conditions,forty metal-organic coordination polymers?CPs?were obtained.They were characterized by IR,elemental analysis,thermogravimetric analysis,X-ray powder diffraction,and X-ray single-crystal diffraction.The luminescent and magnetic properties of some complexes were studied.1.By the reactions of 2,3-pzdc,rare earth nitrates,and ferrous sulfate under hydrothermal conditions,five isostructural FeII-LnIII heterometallic CPs[Ln2Fe?2,3-pzdc?4?H2O?6]·2H2O[Ln=La?1?,Ce?2?,Pr?3?,Nd?4?,Sm?5?]were synthesized.X-ray single-crystal diffraction analysis shows that complexes 1-5 possess a three-dimensional framework with a?4·62?2?42·62·82??63?2?65·8?2 topology.The magnetic properties of complexes1-5 were investigated.2.By the reactions of 2,3-pzdc,rare earth chlorides,and cobalt nitrate under hydrothermal conditions,nine isostructural CoII-LnIII heterometallic CPs[Ln2Co?2,3-pzdc?4?H2O?6]·2H2O[Ln=La?6?,Pr?7?,Nd?8?,Sm?9?,Eu?10?,Gd?11?,Tb?12?]and[Ln2Co?2,3-pzdc?4?H2O?4]·4H2O[Ln=Dy?13?,Er?14?]were synthesized.Complexes 6-14 are basically isostructural with1-5.The magnetic properties of complexes 6-14 were investigated.Complexes 11 and 12 manifest the weak ferromagnetic interactions between CoII and LnIII in the low-temperature range.Complex 13 exhibits a field-induced slow magnetic relaxation behavior.3.By the reactions of 2,3-pzdc,rare earth nitrates,and cupric chloride under hydrothermal conditions,eleven isostructural CuII-LnIII heterometallic CPs[Ln2Cu?2,3-pzdc?4?H2O?6]·2H2O[Ln=La?15?,Pr?16?,Nd?17?,Sm?18?,Eu?19?,Gd?20?,Tb?21?],[Dy2Cu?2,3-pzdc?4?H2O?4]·4H2O?22?,and[Ln2Cu?2,3-pzdc?4?H2O?4]·2H2O[Ln=Er?23?,Yb?24?,Lu?25?]were synthesized.Complexes 15-25 are basically isostructural with 1-5.The magnetic properties of complexes 15-25 were investigated.Complex 21shows a magnetic transition between short-range ferromagnetic ordering at 60K and long-range ferromagnetic ordering below 26 K.Complex 22 displays a field-induced single molecule magnet behavior,with a Ueff value of 102.4 K.4.By the reactions of 2,3-pzdc,rare earth nitrates/rare earth chlorides,and zinc nitrate/cadmium nitrate under hydrothermal conditions,fifteen ZnII/CdII-LnIII/LnIII CPs[Ln2Zn?2,3-pzdc?4?H2O?6]·2H2O[Ln=La?26?,Pr?27?,Nd?28?,Sm?29?,Eu?30?,Tb?31?,Dy?32?],[Ln2Cd?2,3-pzdc?4?H2O?6]·2H2O[Ln=La?33?,Pr?34?,Nd?35?],and[Ln2?2,3-pzdc?3?H2O?5]·3H2O[Ln=Eu?36?,Tb?37?,Dy?38?,Ho?39?,Er?40?]were synthesized.The ZnII/CdII-LnIIIII heterometallic CPs 26-35 are basically isostructural with 1-5.The LnIII CPs36–40 display isostructural three-dimensional framework with a{4.6.8}{4.62.83}topology.The luminescent and magnetic properties of complexes 26–40 were investigated.Complexes 36–38 exhibit the characteristic luminescence of the LnIII ions sensitized by 2,3-pzdc.Complexes 32 and 38 show field-induced slow magnetic relaxation behaviors. |
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