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Two types of lanthanide coordination polymers, namely, [Ln(PA)(NO_3)(DMA)_3]_n(Ln=Gd(1), Dy(2), Eu(3), Tb(4))(type I), and {[Ln_2(PA)_3(DMF)_4]·2DMF}(Ln=Eu(5), Tb(6))(type II)(PA=Pamoic acid, DMA=dimethylacetamide,DMF=N,N-dimethylformamide), have been synthesized by the reaction of Ln(NO_3)_3·6H_2O with pamoic acid through layer diffusion method. These complexes were characterized by single crystal X-ray diffraction, infrared spectroscopy(IR),thermogravimetric analysis(TGA), fluorescence and magnetic measurements. Solvents and lanthanide atoms in the reaction play an important role in controlling different structures. Type I demonstrated 1-D linear chain structure connected by Ln atoms and PA ligands. Type II exhibited non-interpenetrating 3-D 6-connected 4_36~(12) nets based on binuclear [Ln_2(CO_2)_6(DMF)_4] cores.Magnetic properties of complexes 1–4 were investigated in details. Complex 1 shows significant magnetocaloric effect with–ΔS_m=20.37 J kg~(–1) K~(–1) at 3.0 K and 7 T. Complex 2 exhibits slow relaxation of the magnetization. Complexes 3–6 exhibit both ligand- and metal-centered fluorescent properties. Complex 6 demonstrates fluorescent sensing of DMF and Cu~(2+) ion.
(Ln = Gd (1), Dy (2), Eu (3), Tb (4)) (type I) , and [Ln_2 (PA) _3 (DMF) _4] · 2DMF} (Ln = Eu (5), Tb (6)) (type II) dimethylformamide, have been synthesized by the reaction of Ln (NO_3) _3 · 6H_2O with pamoic acid through layer diffusion method. These complexes were characterized by single crystal X-ray diffraction, infrared spectroscopy (IR), thermogravimetric analysis (TGA) and magnetic measurements. Solvents and lanthanide atoms in the reaction play an important role in controlling different structures. Type I demonstrated 1-D linear chain structure connected by Ln atoms and PA ligands. Type II exhibited non-interpenetrating 3-D 6-connected 4_36 Complex 1 shows significant magnetocaloric effect with -ΔS_m = 20.37 J kg ~ (-1) ~ (12) nets based on binuclear [Ln_2 (CO_2) _6 (DMF) ) K ~ (-1) at 3.0 K an Complexes 3-6 exhibit both ligand- and metal-centered fluorescent properties. Complex 6 demonstrates fluorescent sensing of DMF and Cu 2+ ion.