Hexaaqua­manganese(II) tetra­aqua­bis(2-amino­pyrazine-κN 4)manganese(II) disulfate dihydrate

The reaction of manganese(II) sulfate and 2-amino­pyrazine affords the title salt, [Mn(H2O)6][Mn(C4H5N3)2(H2O)4](SO4)2·2H2O. The metal atoms in the tetra­aqua-coordinated and hexa­aqua-coordinated cations lie on centers of inversion in octa­hedral geometries. The cations, anions and solvent water mol­ecules are linked by O—H⋯O, N—H⋯O and O—H⋯N hydrogen bonds into a three-dimensional network

Bis(2-amino­pyrazine-κN 1)tetra­aqua­cadmium(II) bis­(perchlorate)–2-amino­pyrazine (1/4)

In the title compound, [Cd(C4H5N3)2(H2O)4](ClO4)2·4C4H5N3, the CdII atom (site symmetry ) is coordinated by two N-heterocycles and four water mol­ecules, resulting in a distorted trans-CdN2O4 octa­hedral geometry for the metal. In the crystal, the cation, anion and free N-heterocycle mol­ecules are linked by N—H⋯N, N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, forming a three-dimensional network

1,4-Bis(2-pyridylimino­meth­yl)benzene

In the crystal structure of the title compound, C18H14N4, the mol­ecule assumes site symmetry with the centroid of the benzene ring located on the inversion center. The mol­ecule is almost flat, with a dihedral angle of 2.70 (9)° between the pyridine and benzene rings

Aqua­chloridobis(1,10-phenanthroline-κ2 N,N′)zinc(II) chloride N,N-dimethyl­formamide solvate

The Zn atom in the title salt, [ZnCl(C12H8N2)2(H2O)]Cl·C3H7NO, is chelated by two phenanthroline mol­ecules and is bonded to one chloride ion and one water mol­ecule, resulting in a ZnN4ClO octa­hedral coordination environment with the Cl and O atoms in a cis conformation. The cations and anions are linked by O—H⋯Cl hydrogen bonds across a center of inversion, forming a hydrogen-bonded dimeric association. The dimethyl­formamide solvent mol­ecule is disordered over two orientations in a 0.56 (1):0.44 (1) ratio

Tetra­aqua­bis(4-formyl­benzoato-κO)cobalt(II) tetra­hydrate

The CoII atom in the title compound, [Co(C8H5O3)2(H2O)4]·4H2O, which exists in an all-trans octa­hedral coordination geometry, lies on a center of inversion. The coordinated and uncoordinated water mol­ecules engage in extensive hydrogen-bonding inter­actions, forming a three-dimensional hydrogen-bonded network

4-Hydroxy­pyridinium hydrogen sulfate

The crystal structure of the title salt, C5H6NO+·HSO4 −, consists of planar(r.m.s. deviation = 0.001 Å) 4-hydroxy­pyridinium cations and hydrogen sulfate anions which are hydrogen bonded into a layer motif. In the anion, the S—O bond [1.551 (2) Å] involving the O atom bearing the acid H atom is longer than the other three S—O bonds, which range from 1.437 (1) to 1.454 (1) Å

Hexaaqua­cobalt(II) tetra­aqua­bis(2-amino­pyrazine-κN 4)cobalt(II) disulfate dihydrate

The reaction of cobalt(II) sulfate and 2-amino­pyrazine affords the title salt, [Co(H2O)6][Co(C4H5N3)2(H2O)4](SO4)2·2H2O. The metal atoms in the tetra­aqua-coordinated and hexa­aqua-coordinated complex cations lie on centers of inversion in slightly distorted octa­hedral geometries. The cations, anions and solvent water mol­ecules are linked by O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds into a three-dimensional network

Hexaaqua­manganese(II) bis­[4-(pyridin-2-ylmeth­oxy)benzoate] dihydrate

The MnII atom in the title salt, [Mn(H2O)6](C13H10NO3)2·2H2O, lies on a center of inversion in an octa­hedron of water mol­ecules. The cations, anions and uncoordinated water mol­ecules are linked by O—H⋯O and O—H⋯N hydrogen bonds into a three-dimensional network. The anion is essentially planar, with an r.m.s. deviation of all non-H atoms of 0.068 Å