catena-Poly[[aqua­(1,10-phenanthroline)zinc(II)]-μ-maleato-κ³O,O:O′]

In the title compound, [Zn(C₄H₂O₄)(C₁₂H₈N₂)(H₂O)]_n, the octa­hedrally coordinated Zn atom is bonded to two N atoms from phenanthroline, three carboxyl O atoms and one water O atom.

Diaqua­bis(ethyl­enediamine)nickel(II) bis­(4-amino­naphthalene-1-sulfonate) dihydrate

In the title complex, [Ni(C₂H₈N₂)₂(H₂O)₂](C₁₀H₈NO₃S)₂·2H₂O, the Ni atom of the centrosymmetric cation has a distorted octa­hedral coordination geometry, and is bonded to four N atoms, from two diethyl­enediamine ligands, and to two water O atoms. Symmetry-related 4-aminona­phthalene-1-sulfonate anions are antiparallel. The crystal structure is stabilized by π–π inter­actions and N—H...O, O—H...O and O—H...N hydrogen bonds.

Diaqua­bis(ethyl­enediamine-κ²N,N′)copper(II) bis­(4-aminona­phthalene-1-sulfonate) dihydrate

In the title compound, [Cu(C₂H₈N₂)₂(H₂O)₂](C₁₀H₈NO₃S)₂·2H₂O, the Cu^II complex cation, located on an inversion centre, has a distorted octa­hedral coordination geometry formed by two ethyl­enediamine and two water mol­ecules. The distance of 3.4987 (11) Å between the centroids of neighbouring parallel aromatic rings of aminona­phthalenesulfonate anions suggests the existence of π–π stacking.