catena‐Poly[[bis[aqua­(1,10‐phenanthroline)lead(II)]‐di‐μ3‐5‐carboxy‐3‐sulfonatobenzoato] dihydrate]

In the centrosymmetric title polymer, catena‐poly[[bis[aqua­(1,10‐phenanthroline‐κ²N,N′)lead(II)]‐di‐μ₃‐5‐carboxy‐3‐sulfonatobenzoato‐1:2:1′κ⁴O³:O¹,O^1′:O¹;2′:1:2κ⁴O¹:O¹,O^1′:O³] dihydrate], {[Pb(C₈H₄O₇S)(C₁₂H₈N₂)(H₂O)]·H₂O}_n, each seven‐coordinate lead(II) ion is bound by five O atoms from one water molecule and three 5‐sulfoisophthalate (sip) anions, and by two N atoms from a 1,10‐phenanthroline (phen) ligand. The sip sulfonate group is monodentate. One O atom of the sip carboxyl­ate group is chelated to one Pb²⁺ cation, with the other also bridging an adjacent Pb²⁺ cation. The carboxyl group is uncoordinated. This unusual coordination results in a chain structure along the b axis, which is linked by strong intermolecular hydrogen bonds into a three‐dimensional network.