catena-Poly[[[tetra­aqua­manganese(II)]-μ-4,4′-bipyridine] bis­(3-hydroxy­cinnamate) dihydrate]

The title compound, {[Mn(C(10)H(8)N(2))(H(2)O)(4)](C(9)H(7)O(3))(2)·2H(2)O}(n), was obtained by the hydro­thermal reaction of manganese chloride with mixed 3-hydroxy­lcinnamic acid (H(2) L) and 4,4′-bipyridine (4,4′-bipy) ligands. The structure contains [Mn(C(10)H(8)N(2))(H(2)O)(4)](2+) cations with the Mn(II) atoms lying on a centres of inversion and bridged into a linear chain along the a axis by 4,4′-bipy ligands, surrounded by HL (−) anions and uncoordinated water mol­ecules. Extensive O—H⋯O hydrogen-bonding and weak π–π inter­actions [centroid–centroid distance = 3.7572 (3) Å] between the constituents lead to the formation of a three-dimensional supra­molecular network.