catena-Poly[[[di­aqua­bis­(seleno­cyanato-κN)iron(II)]-μ-1,2-bis­(pyridin-4-yl)ethane-κ2 N:N′] 1,2-bis­(pyridin-4-yl)ethane disolvate dihydrate]

The title compound, {[Fe(NCSe)2(C12H12N2)(H2O)2]·2C12H12N2·2H2O} n , was obtained by the reaction of iron(II) sulfate hepta-hydrate and potassium seleno-cyanate with 1,2-bis-(pyridin-4-yl)ethane (bpa) in water. The Fe(II) cation is coordinated by two N-bonded seleno-cyanate anions, two water mol-ecules and two 1,2-bis-(pyridin-4-yl)ethane (bpa) ligands in a slightly distorted octa-hedral geometry. In addition, two non-coordinating bpa mol-ecules and two water mol-ecules are present. The Fe(II) cation is located on a center of inversion while the coordinating bpa ligand is located on a twofold rotation axis. The Fe(II) cations are linked by the bpa ligands into chains along the b-axis direction, which are further connected into layers perpedicular to the c axis by O-H⋯N and O-H⋯O hydrogen bonds to the non-coordin-ating bpa and the water mol-ecules. The crystal studied was twinned by pseudo-merohedry (180° rotation along c*; contribution of the minor twin component 3.7%).