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Updated: May 22, 2026

Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
catena-Poly[[aqua-(2-iodo-benzoato-κO)cobalt(II)]-μ-aqua-μ-2-iodo-benzoato-κ(2)O:O']
Abstract:
The asymmetric unit of the polymeric title compound, [Co(C(7)H(4)IO(2))(2)(H(2)O)(2)](n), contains one Co(II) cation, two iodo-benzoate anions and two water mol-ecules. One iodo-benzoate anion and one water mol-ecule bridge adjacent Co cations, forming a polymeric chain running along the a axis, while the other iodo-benzoate anion and water mol-ecule coordinate in a monodentate manner to the Co(II) cation, completing the slightly distorted octa-hedral geometry. In the two independent anionic ligands, the carboxyl-ate groups are twisted away from the attached benzene rings by 51.38 (18) and 39.89 (11)°, and the two benzene rings are nearly perpendicular to each other with a dihedral angle of 86.09 (10)°. Intra-molecular O-H⋯O hydrogen bonds between coordinating water mol-ecules and adjacent carboxyl-ate O atoms help to stabilize the mol-ecular structure. In the crystal, weak C-H⋯O hydrogen bonds link the polymeric chains into a three-dimentional supra-molecular network.
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