A new polymorph of aqua­bis­(1,10-phenanthroline-κ²N,N′)copper(II) dinitrate

The title mol­ecule, [Cu(C₁₂H₈N₂)₂(H₂O)](NO₃)₂, is a new polymorph of a compound which up to now has been reported to crystallize space groups in C2/c and Cc. The crystal studied was twinned by non-merohedry (final BASF factor of 0.40043) with the structure being solved and refined in P-1. The Cu^II atom is coordinated by four N atoms from two 1,10-phenanthroline ligands and an O atom from a water mol­ecule in an approximate trigonal–bipyramidal geometry. Discrete entities of one cation and two nitrate anions are formed by water–nitrate O—H...O hydrogen bonds. The components are further assembled into a three-dimensional network by C—H...O hydrogen bonds.

Bis(2,2′-bipyridyl-κ²N,N′)chloridonickel(II) nitrate trihydrate

In the title hydrated salt, [NiCl(C₁₀H₈N₂)₂](NO₃)·3H₂O, the Ni²⁺ ion is coordinated by two 2,2′-bipyridyl (2,2′-bpy) ligands and a chloride ion in a trigonal–bipyramidal geometry. The chloride ion occupies an equatorial site and the dihedral angle between the 2,2′-bpy ring systems is 72.02 (6)°. In the crystal, the components are linked by C—H...O and O—H...O hydrogen bonds and aromatic π–π stacking inter­actions [shortest centroid–centroid separation = 3.635 (2) Å], generating a three-dimensional network.

Crystal structure of N,N-di­ethyl­benzene-1,4-diaminium dinitrate

In the structure of the title mol­ecular salt, C₁₀H₁₈N₂²⁺·2NO₃⁻, the dinitrate salt of 4-(N,N-di­ethyl­amino)­aniline, the two ethyl groups lie almost perpendicular to the plane of the benzene ring [the ring-to-ethyl C—C—N—C torsion angles are −59.5 (2) and 67.5 (3)°]. The aminium groups of the cation form inter-species N—H...O hydrogen bonds with the nitro O-atom acceptors of both anions, giving rise to chain substructures lying along c. The chains are linked via further N—H...O hydrogen bonds, forming two-dimensional networks lying parallel to (010). These sheets are linked by C—H...O hydrogen bonds, forming a three-dimensional structure.