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Poly[[tri-μ(3)-hydroxido-tris-(μ(4)-pyridine-2,5-dicarboxyl-ato)trineodymium(III)] monohydrate]
Qing Zhang1, Xing Wang, Shen-Tang Wang
1School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
Abstract:
In the title compound, {[Nd(3)(C(7)H(3)NO(4))(3)(OH)(3)]·H(2)O}(n), the Nd(III) atom is eight-coordinated by the three O atoms of three asymmetrically μ(3)-bridging hydroxide groups, by four carboxyl-ate O atoms of four different pyridine-2,5-dicarboxyl-ate (2,5-pydc) ligands, and by the N atom of a 2,5-pydc ligand. Six Nd atoms are connected by six hydroxide groups, forming an [Nd(6)(μ(3)-OH)(6)] cluster unit of symmetry -3 and a slightly compressed octa-hedral geometry. Adjacent [Nd(6)(μ(3)-OH)(6)] clusters are connected by the 2,5-pydc ligands, via O and N atoms, forming chains along the c axis. The remaining O atoms of the 2,5-pydc ligands link these chains into a three-dimensional framework. A disordered water molecule, located on a threefold rotation axis at the opposite side of the [Nd(6)(μ(3)-OH)(6)] cluster and exposed to each of the three Nd atoms, completes the structure.
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