metal-organic compounds
Open access
The title compound, {[Co(C10H8N2)2(H2O)2](NO3)2·4H2O}n, (C10H8N2 = 4,4′-bipyridine = 4,4′-bpy) is a layered coordination polymer built up from a cationic square grid extending in (101) enclosing uncoordinating nitrate ions and water molecules. The CoII ion has site symmetry 2 and one of the 4,4′-bpy ligands is generated by twofold symmetry [two N atoms and two C atoms lie on the rotation axis and the dihedral angle between the pyridine rings is 45.66 (5)°]. The other 4,4′-bpy ligand is generated by a crystallographic inversion center. The CoII ion exhibits a slightly distorted octahedral coordination geometry defined by two O atoms of two coordinating water molecules and four N atoms from four bridging 4,4′-bpy ligands. The structure is consolidated by O—HO, C—HO and C—HN hydrogen bonds.
metal-organic compounds
Open access
The title salt, (C7H11N2)[FeCl4], consists of one essentially planar (the r.m.s. deviation for all non-H atoms being 0.004 Å) 4-(dimethylamino)pyridinium cation and a tetrahedral tetrachloridoferrate(III) anion. The cations and anions are arranged in layers parallel to (010). Besides electrostatic interactions, the crystal packing features N—HCl and C—HCl hydrogen bonds between cations and anions, forming a three-dimensional network.