Tetrakis[μ-4-(methylamino)benzoato-κ2O:O′]bis[(N,N-diethylnicotinamide-N1)zinc(II)] dihydrate

The title molecule, [Zn2(C8H8NO2)4(C10H14N2O)2]·2H2O, is a centrosymmetric binuclear complex, with two ZnII ions [Zn...Zn' = 2.9301 (4) Å] bridged by four methylaminobenzoate (MAB) ligands. The four nearest O atoms around each ZnII ion form a distorted square-planar arrangement with the distorted square-pyramidal coordination completed by the pyridine N atom of the N,N-diethylnicotinamide (DENA) ligand. Each ZnII ion is displaced by 0.3519 (2) Å from the plane of the four O atoms, with an average Zn—O distance of 2.030 Å. The dihedral angles between carboxylate groups and adjacent benzene rings are 10.57 (10) and 16.63 (12)°, while the benzene rings are oriented at a dihedral angle of 81.84 (5)°. The pyridine ring is oriented at dihedral angles of 40.49 (6) and 51.25 (6)° with respect to the benzene rings. In the crystal structure, intermolecular O—H...O and N—H...O hydrogen bonds link the molecules into a three-dimensional network. The π–π contact between the inversion-related pyridine rings [centroid–centroid distance = 3.633 (1) Å] may further stabilize the crystal structure