Bis(4-amino­pyridinium) hexa­aqua­nickel(II) bis­(sulfate)

In the title compound, (C₅H₇N₂)₂[Ni(H₂O)₆](SO₄)₂, the Ni^II cation is located on an inversion centre and is coordinated by six aqua ligands in a slightly distorted octa­hedral coordination environment. The [Ni(H₂O)₆]²⁺ ions are connected through an extensive network of O—H...O hydrogen bonds to sulfate anions, leading to the formation of layers parallel to (001). The 4-amino­pyridinium cations are located between these layers and are connected to the anionic framework by N—H...O hydrogen bonds. Weak π–π inter­actions between the pyridine rings, with a centroid–centroid distance of 3.754 (9) Å, provide additional stability to the crystal packing.

Hexa­kis­(3-chloro-2-methyl­anilinium) cyclo­hexa­phosphate dihydrate

In the organic/inorganic salt hydrate, 6C₇H₉ClN⁺·P₆O₁₈⁶⁻·2H₂O, the cyclo­hexa­phosphate anion resides on an inversion centre. The asymmetric unit consists of three cations, one half-anion and a water mol­ecule. In the crystal, the water mol­ecules and the [P₆O₁₈]⁶⁻ anions are linked by O—H...O hydrogen bonds, generating infinite layers parallel to the ab plane. These layers are inter­connected by the organic cations through N—H...O hydrogen bonds.

Propane-1,2-di­ammonium chromate(VI)

In the title mol­ecular salt, (C₃H₁₂N₂)[CrO₄], each chromate anion accepts six N—H...O and C—H...O hydrogen bonds from nearby propane-1,2-di­ammonium cations. Three of the four O atoms of the chromate anion accept these bonds; the remaining Cr—O bond length is notably shorter than the others. In the crystal, the anions and cations stack in layers lying parallel to (100): the hydrogen-bonding pattern leads to a three-dimensional network.

Bis(2,6-di­methyl­anilinium) di­aqua­bis­(di­hydrogen diphosphato-κ²O,O′)cobaltate(II)

In the title compound, (C₈H₁₂N)₂[Co(H₂P₂O₇)₂(H₂O)₂], the Co²⁺ ion lies on a crystallographic inversion centre and adopts a slightly distorted octa­hedral CoO₆ coordination geometry arising from two chelating diphosphate [H₂P₂O₇]²⁻ ligands and two trans water mol­ecules. In the crystal, the components are linked by O—H...O, N—H...O and C—H...O hydrogen bonds and weak aromatic π–π stacking [shortest centroid–centroid separation = 3.778 (2) Å] inter­actions. (001) layers of alternating organic cations and complex inorganic anions are apparent.

Bis[tris­(phenanthroline-κ²N,N′)cobalt(II)] undeca­tungsto(VI)vanado(V)phosphate dihydrate

In the title hydrated salt, [Co(C₁₂H₈N₂)₃]₂[PVW₁₁O₄₀]·2H₂O, the complete Kegggin ion is generated by crystallographic inversion symmetry, which imposes statistical disorder on the O atoms of its central PO₄ group. The V atom is statistically disordered over all the metal sites of the anion. In the cation, the Co²⁺ ion is coordinated by three bidentate 1,10-phenanthroline (phen) ligands, generating a distorted CoN₆ octa­hedron. Possible very weak intra­molecular C—H...π inter­actions occur in the cation. In the crystal, the components are linked by O—H...O and C—H...O inter­actions, building a three-dimensional network featuring one-dimensional voids along the c-axis direction.

1-Phenyl­piperazine-1,4-diium tetra­chlorido­cobalt(II)

In the title mol­ecular salt, (C₁₀H₁₆N₂)[CoCl₄], the piperazine ring of the phenyl­piperazine dication adopts a chair conformation and the phenyl ring occupies an equatorial orientation. In the tetra­chlorido­cobaltate(II) dianion, the Co—Cl bond lengths for the chloride ions not accepting hydrogen bonds are significantly shorter than those for the chloride ions accepting such bonds. In the crystal, the components are linked by N—H...Cl hydrogen bonds, generating [001] chains.

Bis(2-meth­oxy­benzyl­ammonium) di­aqua­bis­(di­hydrogen diphosphato-κ²O,O′)cobaltate(II) dihydrate

The title compound, (C₈H₁₂NO)₂[Co(H₂P₂O₇)₂(H₂O)₂]·2H₂O, crystallizes isotypically with its Mn^II analogue. It consists of alternating layers of organic cations and inorganic complex anions, extending parallel to (100). The complex cobaltate(II) anion exhibits -1 symmetry. Its Co²⁺ atom has an octa­hedral coordination sphere, defined by two water mol­ecules in apical positions and two H₂P₂O₇²⁻ ligands in equatorial positions. The cohesion between inorganic and organic layers is accomplished by a set of O—H...O and N—H...O hydrogen bonds involving the organic cation, the inorganic anion and the remaining lattice water mol­ecules.

Tri­chlorido­(1-ethyl­piperazin-1-ium)cobalt(II)

In the title complex, [Co(C₆H₁₅N₂)Cl₃], the Co²⁺ ion is coordinated in a distorted tetra­hedral fashion by three chloride ions and one N atom of the piperazine ring; the ring adopts a chair conformation with the N—Co and N—C_Et bonds in equatorial orientations. In the crystal, mol­ecules are connected by N—H...Cl hydrogen bonds, generating (10-1) sheets.

Piperazine-1,4-diium bis­(hexa­hydroxido­hepta­oxidohexa­borato-κ³O,O′,O′′)cobaltate(II) hexa­hydrate

In the title hydrate, (C₄H₁₂N₂)[Co{B₆O₇(OH)₆}₂]·6H₂O, both the dication and dianion are generated by crystallographic inversion symmetry. The Co²⁺ ion in the dianion adopts a fairly regular CoO₆ octa­hedral coordination geometry arising from the two O,O′,O′′-tridentate ligands. In the crystal, the dianions and water mol­ecules are linked by O—H...O hydrogen bonds, generating a framework with large [100] channels, which are occupied by the organic dications. N—H...O and C—H...O hydrogen bonds consolidate the structure.

1,1,4,7,7-Penta­methyl­diethylenetri­ammonium trinitrate

In the title compound, C₉H₂₆N₃³⁺·3NO₃⁻, the triprotonated 1,1,4,7,7-penta­methyl­diethylenetri­amine mol­ecules are linked to the nitrate anions by multiple bifurcated N—H...(O,O) and weak C—H...O hydrogen bonds. The organic cation is characterized by N—C—C—N torsion angles of −176.2 (2) and 176.6 (2)°.

1-Methyl­piperazine-1,4-dium bis­(hydrogen oxalate)

In the crystal structure of the title compound, C₅H₁₄N₂²⁺·2HC₂O₄⁻, the two crystallographically independent hydrogen oxalate anions are linked by strong inter­molecular O—H...O hydrogen bonds, forming two independent corrugated chains parallel to the b axis. These chains are further connected by N—H...O and C—H...O hydrogen bonds originating from the organic cations, forming a three-dimensional network. The diprotonated piperazine ring adopts a chair conformation, with the methyl group occupying an equatorial position.

Tetra­kis(2-amino-5-chloro­pyridinium) di­hydrogen cyclo­hexa­phosphate

In the crystal structure of the title compound, 4C₅H₆ClN₂⁺·H₂P₆O₁₈⁴⁻, the [H₂P₆O₁₈]⁴⁻ anions are interconnected by O—H...O hydrogen bonds, leading to the formation of infinite ribbons extending along the a-axis direction. These ribbons are linked to the organic cations, via N—H...O and C—H...O hydrogen bonds, into a three-dimensional network. The six P atoms of the [H₂P₆O₁₈]⁴⁻ anion form a chair conformation. The complete cyclohexaphosphate anion is generated by inversion symmetry.

m-Xylylenediaminium dinitrate

The asymmetric unit of the title salt, C₈H₁₄N₂²⁺·2NO₃⁻, contains two independent dications and four independent nitrate anions. The crystal structure consists of discrete nitrate ions, three of which stack in layers parallel to (001) at z = 0 and 0.5. These layers are connected via m-xylylenediaminium dications. The fourth anion is sandwiched by the two independent organic cations in the asymmetric unit. In the crystal, the ions are connected by a large number of bifurcated and non-bifurcated N—H...O(O) hydrogen bonds, forming sheets parallel to (100). These sheets are connected by C—H...O hydrogen bonds, forming a three-dimensional network.

Crystal structure of 2,5-di­methyl­anilinium hydrogen maleate

The crystal structure of the title salt, C₈H₁₂N⁺·C₄H₃O₄⁻, consists of a 2,5-di­methyl­anilinium cation and an hydrogen maleate anion. In the anion, a strong intra­molecular O—H...O hydrogen bond is observed, leading to an S(7) graph-set motif. In the crystal, the cations and anions pack in alternating layers parallel to (001). The ammonium group undergoes inter­molecular N—H...O hydrogen-bonding inter­actions with the O atoms of three different hydrogen maleate anions. This results in the formation of ribbons extending parallel to [010] with hydrogen-bonding motifs of the types R⁴₄(12) and R⁴₄(18).