Polydodeca­aqua­bis­(μ3-pyridine-26-dicarboxyl­ato)tetra­kis­(μ2-pyridine-26-dicarboxyl­ato)tri­calciumdieuropium(III) 10.5-hydrate

摘要

In the title compound, {[Ca3Eu2(C7H3NO4)6(H2O)12]·10.5H2O}n, the Eu^III ion is nine-coordinated by three tridentate pyridine-2,6-dicarboxyl­ate (PDA) ligands, forming a [Eu(PDA)3]³⁻ building block. The Ca²⁺ ions adopt two types of coordination geometries. One Ca²⁺ ion, lying on a twofold rotation axis, is eight-coordinated by four carboxyl­ate O atoms from four PDA ligands and four water mol­ecules, and the other two Ca²⁺ ions, each lying on an inversion center, are six-coordinated by two carboxyl­ate O atoms from two PDA ligands and four water mol­ecules. The carboxyl­ate groups bridge the Eu^III and Ca²⁺ ions into a three-dimensional porous framework, with channels extending along [010] and [001] in which lattice water mol­ecules are located. Two of the lattice water mol­ecules are disordered over two sets of sites with equal occupancy and one water mol­ecule is 0.25-occupied. Numerous O—H⋯O hydrogen bonds involving the water mol­ecules and carboxyl­ate O atoms are present.