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Updated: May 11, 2026

Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Three novel 1D lanthanide-carboxylate polymeric complexes: syntheses, crystal structures and magnetic analyses
Jumei Tian1, Bo Li, Xiaoying Zhang
1Faculty of Chemistry, Northeast Normal University, Changchun 130024, China.
Abstract:
Three novel one-dimensional (1D) lanthanide coordination complexes involving the 4-methyl-3-nitrobenzoic acid (HL) ligand, with the general formulae [Gd(L)3(H2O)(CH3OH)] (1), [Gd(L)3(H2O)2]·(4,4'-bpy)·CH3OH (2), [Dy(L)3(H2O)(CH3OH)] (3), have been synthesized by solvothermal reactions. These complexes have been structurally characterized by single-crystal X-ray diffraction, IR, PXRD, TGA, and elemental analysis. Complexes 1 and 3 are isostructural except for the distinction of the metal ion. Magnetic measurements indicate that complexes 1-3 show antiferromagnetic behaviors. Complex 3 behaves with slow relaxation of the magnetization, where the frequency-dependent out-of-phase signals are noticed. However, the characteristic maxima were not reached above 2 K under zero direct current (DC) fields. When a DC field of 5000 Oe was employed, the frequency dependent peaks of alternating current (AC) signals were obtained.
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