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Updated: May 26, 2026

An Aptamer-based Sensor for Unchelated Gadolinium(III)
Published on: January 9, 2017
Poly[[tetra-aqua-(μ(4)-imidazole-4,5-dicarboxyl-ato)(μ(3)-imidazole-4,5-dicarboxyl-ato)-μ(3)-sulfato-μ(2)-sulfato-cob
1School of Chemistry and Environment, South China Normal University, Guangzhou 510631, People's Republic of China.
Abstract:
The asymmetric unit of the title compound, {[CoGd(2)(C(5)H(2)N(2)O(4))(2)(SO(4))(2)(H(2)O)(4)]·H(2)O}(n), contains one Co(II) ion, two Gd(III) ions, two imidazole-4,5-dicarboxyl-ate ligands, two SO(4) (2-) anions, four coordinated water mol-ecules and one uncoordinated water mol-ecule. The Co(II) ion is six-coordinated by two O atoms from two coordinated water mol-ecules, as well as two O atoms and two N atoms from two imidazole-4,5-dicarboxyl-ate ligands, giving a slightly distorted octa-hedral geometry. Both Gd(III) ions are eight-coordinated in a distorted bicapped trigonal-prismatic geometry. One Gd(III) ion is coordinated by four O atoms from two imidazole-4,5-dicarboxyl-ate ligands, three O atoms from three SO(4) (2-) anions and a water O atom; the other Gd(III) ion is bonded to five O atoms from three imidazole-4,5-dicarboxyl-ate ligands, two O atoms from two SO(4) (2-) anions as well as a water O atom. These metal coordination units are connected by bridging imidazole-4,5-dicarboxyl-ate and sulfate ligands, generating a heterometallic layer parallel to the ac plane. The layers are stacked along the b axis via N-H⋯O, O-H⋯O, and C-H⋯O hydrogen-bonding inter-actions, generating a three-dimensional framework.
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