The monoclinic form of di-μ-aqua-bis­[diaqua­bis­(thio­cyanato-κN)iron(II)]–1,4-bis­(4H-1,2,4-triazol-4-yl)benzene (1/3)

The title complex, [Fe₂(NCS)₄(H₂O)₆]·3C₁₀H₈N₆, comprises two Fe^II atoms octahedrally coordinated and bridged by two aqua O atoms that straddle a crystallographic inversion center, forming a quadrilateral core. The water ligands of the core are involved in hydrogen bonds with the triazole N atoms of the organic mol­ecules, which generates a layer motif in the ab plane. There are π–π stacking inter­actions between benzene rings of 3.490 (6) Å, and between triazole rings of 3.543 (8) and 3.734 (7) Å in neighboring layers, forming a three-dimensional network.

The triclinic form of di-μ-aqua-bis­[diaqua­bis­(thio­cyanato-κN)iron(II)]–1,4-bis­(4H-1,2,4-triazol-4-yl)benzene (1/3)

In the title compound, [Fe₂(NCS)₄(H₂O)₆]·3C₁₀H₈N₆, the centrosymmetric dinuclear complex contains two Fe^II ions bridged by two aqua ligand O atoms, forming a four-membered ring. The slightly distorted octa­hedral coordination environment of the two Fe^II ions is completed by two monodentate aqua ligands and two thio­cyanate ligands. One of the 1,4-bis­(4H-1,2,4-triazol-4-yl)benzene mol­ecules lies across an inversion center. In the crystal, O—H...N hydrogen bonds connect the components, forming a two-dimensional network parallel to (011). In addition, π–π stacking inter­actions involving the benzene and triazole rings, with centroid–centroid distances in the range 3.502 (5)—3.787 (6) Å, connect the two-dimensional hydrogen-bonded network into a three-dimensional network.

Diaquabis­(thio­cyanato-κN)bis[6-(4H-1,2,4-triazol-4-yl-κN¹)pyridin-2-amine]­cadmium

In the title compound, [Cd(NCS)₂(C₇H₇N₅)₂(H₂O)₂], the Cd^II cation lies on an inversion center and is coordinated by the N atoms of two thiocyanate anions, by N atoms of two 6-(4H-1,2,4-triazol-4-yl)pyridin-2-amine ligands and by the O atoms of two water molecules in a distorted N₄O₂ octa­hedral geometry. The dihedral angle between the triazole and pyridine rings is 23.15 (12)°. In the crystal, mol­ecules are linked by N—H...N and O—H...S hydrogen bonds. Offset π–π stacking between parallel pyridine rings of adjacent mol­ecules is also observed, the centroid–centroid distance being 3.6319 (14) Å.

Poly[aqua-μ-bromido-(μ₂-5-methyl­pyrazine-2-carboxyl­ato-κ⁴N¹,O²:O²,O^2′)lead(II)]

In the title coordination polymer, [PbBr(C₆H₅N₂O₂)(H₂O)]_n, the Pb^II atom is coordinated by one pyrazine N atom, two bridging Br atoms, a water mol­ecule and three carboxyl­ate O atoms. Bridging by the two anions generates a layer structure parallel to (001); the layers are linked by O—H...N and O—H...Br hydrogen bonds, forming a three-dimensional network. The lone pair is stereochemically active, resulting in a Ψ-dodeca­hedral coordination environment for Pb^II.

1,4-Bis(4H-1,2,4-triazol-4-yl)benzene dihydrate

The asymmetric unit of the title compound, C₁₀H₈N₆·2H₂O, comprises half the organic species, the mol­ecule being completed by inversion symmetry, and one water mol­ecule. The dihedral angle between the 1,2,4-triazole ring and the central benzene ring is 32.2 (2)°. The water mol­ecules form O—H...N hydrogen bonds with N-atom acceptors of the triazole rings. C—H...N hydrogen bonds are also observed, giving a three-dimensional framework.

N-(Naphthalen-1-yl­methyl­idene)-4H-1,2,4-triazol-4-amine

In the title mol­ecule, C₁₃H₁₀N₄, the dihedral angle between the triazole ring and the naphthalene ring system is is 56.1 (2)°. In the crystal, mol­ecules are connected by weak C—H...N hydrogen bonds into chains along [100]. A short intra­molecular C—H...N contact is also observed.