A novel dinuclear bismuth(III) coordination compound: bis(μ-pyridine-2,6-dicarboxylato)-κ4O2,N,O6:O6′;κ4O2:O2′,N,O6-bis[(azido-κN)(1,10-phenanthroline-κ2N,N′)bismuth(III)] tetrahydrate

A novel dinuclear bismuth(III) coordination compound, [Bi-2(C7H3NO4)(2)(N-3)(2)(C12H8N2)(2)]center dot 4H(2)O has been synthesized by an ionothermal method and characterized by elemental analysis, energy-dispersive X-ray spectroscopy, IR, X-ray photoelectron spectroscopy and single-crystal X-ray diffraction. The molecular structure consists of one centrosymmetric dinuclear neutral fragment and four water molecules. Within the dinuclear fragment, each Bi-III centre is seven-coordinated by three O atoms and four N atoms. The coordination geometry of each Bi-III atom is distorted pentagonal-bipyramidal (BiO3N4), with one azide N atom and one bridging carboxylate O atom located in axial positions. The carboxylate O atoms and water molecules are assembled via O-H center dot center dot center dot O hydrogen bonds, resulting in the formation of a three-dimensional supramolecular structure. Two types of pi-pi stacking interactions are found, with centroid-to-centroid distances of 3.461 (4) and 3.641 (4) angstrom.