Poly[[tetraaquadi-[mu]4-glutarato-[mu]2-terephthalato-dineodymium(III)] heptadecahydrate]

• Published in: Acta crystallographica. Section C, Crystal structure communications Crystal structure communications, 2010-12, Vol.66 (12), p.m371
• Main Authors: Zehnder, Ralph A, Fontaine, Nick C, Zeller, Matthias, Renn, Robert A
• Format: Article
• Language: English
• Subjects: Chemical bonds; Chemical compounds; Crystal structure; Crystallography; Molecules
• ISSN: 0108-2701; 1600-5759
• DOI: 10.1107/S0108270110044872

The title compound, [Nd2(C5H6O4)2(C8H4O4)(H2O)4]·17H2O, obtained via hydrothermal reaction of Nd2O3 with glutaric acid and terephthalic acid, assembles as a three-dimensional open framework with ten-coordinate Nd-O polyhedra. The asymmetric part of the unit cell contains half a glutarate anion, a quarter of a terephthalate dianion, half an NdIII cation, one coordinated water molecule and 4.25 solvent water molecules. Each [NdO10] coordination polyhedron is comprised of six O atoms originating from four glutarate anions, two others from a terephthalate carboxylate group, which coordinates in a bidentate fashion, and two from water molecules. The Nd--O distances range from 2.4184(18) to 2.7463(18)Å. The coordination polyhedra are interconnected by the glutarate anions, extending as a two-dimensional layer throughout the bc plane. Individual two-dimensional layers are interlinked via terephthalate anions along the a axis. This arrangement results in rectangular-shaped cavities with interstices of approximately 3.5 × 6 × 6.5Å (approximately 140Å3), which are occupied by water molecules. The NdIII cations, terephthalate anions, glutarate anions and one of the interstitial water molecules are located on special crystallographic positions. The Nd-terephthalate-Nd units are located across twofold rotation axes parallel to [100], with the NdIII cations located directly on these axes. In addition, the terephthalate anion is bisected by a crystallographic mirror plane perpendicular to that axis, thus creating an inversion centre in the middle of the aromatic ring. The glutarate ligand is bisected by a crystallographic mirror plane perpendicular to (001). One of the solvent water molecules lies on a site of 2/m symmetry, and the symmetry-imposed disorder of its H atoms extends to the H atoms of the other four solvent water molecules, which are disordered over two equally occupied and mutually exclusive sets of positions. [PUBLICATION ABSTRACT]