Bis(μ-2-carboxymethyl-2-hydroxybutanedioato)bis[diaquamanganese(II)]-1, 2-bis(pyridin-4-yl)ethene-water (1/1/2)

The asymmetric unit of the title compound, [Mn2(C6H6O7)2(H ₂O)4]·C12H10N2·2H₂O, contains half of the centrosymmetric Mn complex dimer, half of a 1,2-bis(pyridin-4-yl)ethene molecule, which lies across an inversion center, and one water molecule. Two citrate ligands bridge two Mn^II ions, and each Mn^II atom is coordinated by four O atoms from the citrate ligands (one from hydroxy and three from carboxylate groups) and two water O atoms, forming a distorted octahedral environment. In the crystal, O-H⋯O and O-H⋯N hydrogen bonds link the centrosymmetric dimers and lattice water molecules into a three-dimensional structure which is further stabilized by intermolecular π-π interactions [centroid-centroid distance = 3.959 (2) Å]. Weak C-H⋯O hydrogen bonding interactions are also observed.