Crystal structure of diaquadidysprosium triglutarate tetrahydrate, Dy2(H2O)2[O2C(CH2)3CO2]3 · 4H2O

Abstract

Source of material 0.0396 g (0.30 mmol) glutaric acid and 0.0595 g (0.30 mmol) 1,10-phenanthroline monohydrate were added to a stirred aqueous solution of Dy(NO3)3 · 5H 2 O (0.1316 g, 0.30 mmol) in 10 ml doubly-distilled water. The resulting mixture (pH = 5.0) was loaded into a 23 ml Teflon-lined stainless steel autoclave, which was heated at 170°C for three days, affording colorless crystals. The composition was confirmed by thermogravimetric analyses (weight loss for six moles of H2O molecules per formula unit: calc. 13.13 %, obs. 12.8 % over 25°C 188°C). DiscussionThe title compound was initially reported by Serpaggi and FéreyThe asymmetric unit of the present dysprosium glutarate contains a Dy 3+ cation, one and a half glutarate anions, an aqua ligand and two lattice H2O molecules. The hydrogen atoms of the lattice water molecules were not localized. One glutarate anion (O1, O2, C1 to C3) is located on the twofold rotation axis passing through C3 atom and assumes an anti/anti conformation with non-hydrogen atoms nearly coplanar, while the other dicarboxylate ion (O3 to O6, C4 to C8) adopts an anti/gauche conformation. One lattice H2O molecule (O8) is disordered over four sites with equal occupancies. The large temperature displacement parameters for O9 atom suggest that the water molecules of O9 are disordered ones. The Dy atoms are each coordinated by nine oxygen atoms of one aqua ligand, one anti/anti and four anti/gauche conformational glutarate anions to form distorted mono-capped tetragonal antiprism DyO9 with d(DyO) = 2.344 Å 2.669 Å, ÐODyO = 65.9° 162.3°being comparable with those observed in the literature [3,4]. The anti/anti conformational dicarboxylate bischelate two Dy atoms, and as far as the anti/gauche one is concerned, each terminal carboxylate group chelates one Dy atom with one oxygen atom additionally bonded to second metal atom. Through O3, O6 and their symmetry related partners, the DyO9 polyhedra are edge-shared to generate 1D metal-oxygen chains extending in the [100] direction and the resulting chains are then bridged by the anti/gauche conformational glutarate anions into 2D brick-wall parallel to (001), which are further linked by the bischelating dicarboxylate anions to form 3D framework with the tunnels in the [100] direction filled with the lattice H2O molecules. The glutarate anions exhibit normal bonding values comparable with those reported in the literature [5][6][7].