Poly[[diaqua­tetra­kis­(μ₂-benzene-1,4-di­carbonitrile-κ²N:N′)iron(II)] bis­[tetra­chlorido­ferrate(III)] nitro­methane tetra­solvate]

In the title compound, {[Fe^II(C₈H₄N₂)₂(H₂O)₂][Fe^IIICl₄]₂·4CH₃NO₂}_n, the Fe^II and Fe^III ions are hexa- and tetra­coordinated, respectively. Each unique benzene-1,4-dicarbonitrile mol­ecule lies across a crystallographic inversion centre and bridges two Fe^II ions (each situated on an inversion centre), generating two-dimensional (4,4) square grid layers. The tetra­chloridoferrate(III) anions and nitro­methane solvent mol­ecules lie between the square grid layers and are further link to the adjacent layers into a three-dimensional supra­molecular structure through O—H...Cl and O—H...O hydrogen bonds.

Poly[octakis(1H-imidazole-κN³)octa-μ-oxido-tetra­oxidodicopper(II)tetra­vanadate(V)]

In the title inorganic–organic hybrid compound, [Cu₂V₄O₁₂(C₃H₄N₂)₈]_n, the V^V ion is tetra­coordinated by four O atoms and the Cu^II ion is hexa­coordinated by four N atoms from four imidazole ligands and two O atoms from two tetra­hedral vanadate (VO₄) units in a distorted octa­hedral geometry. The structure consists of two-dimensional sheets constructed from centrosymmetric cyclic [V₄O₁₂]⁴⁻ anions covalently bound through O to [Cu(imidazole)₄]²⁺ cations. Adjacent sheets are linked by N—H...O hydrogen bonds and weak C—H...π inter­actions (H...centroid distances = 2.59, 2.66, 2.76, 2.91 and 2.98 Å into a three-dimensional supra­molecular network.

Tetra­aqua­(2,2′-bipyridine-κ²N,N′)nickel(II) sulfate

The asymmetric unit of the title complex, [Ni(C₁₀H₈N₂)(H₂O)₄]SO₄, consists of a complex [Ni(bipy)(H₂O)₄]²⁺ cation (bipy = 2,2′-bipyridine) and a non-coordinating [SO₄]²⁻ anion. The Ni^II atom is six-coordinated in a distorted octa­hedral geometry defined by the two N atoms of the bipy ligand and four water O atoms. The crystal structure contains extensive classical O—H...O hydrogen bonds, which link the ions into a two-dimensional array in the ab plane. Layers are connected into a three-dimensional supra­molecular structure by C—H...O inter­actions.

trans-Bis(nitrato-κO)bis­(1,10-phenanthroline-κ²N,N′)manganese(II)

In the title compound, [Mn(NO₃)₂(C₁₂H₈N₂)₂], the Mn^II atom lies on a twofold rotation axis, and is six-coordinated in a distorted trans-N₄O₂ octa­hedral environment by four N atoms from two 1,10-phenanthroline ligands and two O atoms from two nitrate anions. The nitrate anion is disordered about a twofold rotation axis with fixed occupancy factors of 0.5. In the crystal, mol­ecules are linked by weak C—H...O hydrogen bonds and π–π stacking inter­actions [centroid–centroid distance = 4.088 (5) Å] into a three-dimensional supra­molecular network.

Poly[aqua­(μ₂-pyrimidine-2-carboxyl­ato-κ⁴O,N:O′,N′)(nitrato-κO)cadmium]

In the title polymer, [Cd(C₅H₃N₂O₂)(NO₃)(H₂O)]_n, the Cd^II atom is seven-coordinate in a distorted capped octa­hedral geometry by two N atoms of two different pyrimidine dicarboxyl­ate (pmc) ligands, three O atoms from three separate pmc ligands, and two O atoms of disordered nitrate anions or water mol­ecules. The Cd^II atoms are bridged by the pmc ligands in a chelating/bridging bis-bidentate and chelating bidentate mode, forming sheets parallel to (20-1). The sheets are further linked into a three-dimensional supra­molecular network via classical O—H...O hydrogen bonds involving the nitrate anions and coordinating water mol­ecules. Intra­molecular O—H...O hydrogen bonding is also observed. The non-coordinating nitrate O atoms are disordered over two sets of sites with occupancies of 0.57 (7) and 0.43 (7).