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Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
catena-Poly[[[tetra-aqua-lanthanum(III)]-di-μ-isonicotinato-κ(4)O:O'] chloride]
1Department of Chemical and Life Science, Baise University, Baise 533000, People's Republic of China.
Abstract:
In the title compound, {[La(C(6)H(4)NO(2))(2)(H(2)O)(4)]Cl}(n), the La(III) atom lies on a twofold rotation axis and is eight-coordinated by four O atoms from four isonicotinate ligands and four water mol-ecules in a distorted square-anti-prismatic coodination environment. Adjacent La(III) atoms are bridged by two carboxyl-ate groups from two isonicotinate ligands, forming an extended chain along [001]. These chains are linked through O-H⋯N hydrogen bonds into a three-dimensional network with channels in which the chloride anions form O-H⋯Cl hydrogen bonds. Intra-chain O-H⋯O hydrogen bonds and π-π inter-actions [centroid-centroid distance = 3.908 (2) Å] are also observed.
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