Poly[[bis[aqua(1,10-phenanthroline)lanthanum(III)]-mu-aqua-di-mu-5-sulfonatoisophthalato] monohydrate] and poly[[[triaqualanthanum(III)]-mu-5-sulfonatoisophthalato] monohydrate].

In the two related polymeric title compounds, [[La2(sip)2(phen)2(H2O)3].H2O]n [sip is the 5-sulfonatoisophthalate trianion (C8H3O7S3-) and phen is 1,10-phenanthroline (C12H8N2)], (I), and [[La(sip)(H2O)3].H2O]n, (II), the lanthanum(III) ions are nine-coordinate, with similar distorted monocapped square-antiprism coordination geometry. The two crystal structures are very different. In (I), the sip anion acts as a pentadentate ligand, one of the coordinated water molecules lies on a twofold axis and further inversion, n-glide and translation operations generate a two-dimensional framework. In (II), the sip anion functions as a hexadentate ligand and a three-dimensional network with trinuclear 24-membered rings is developed via inversion, n-glide, twofold-screw and translation operations. Both structures also have extensive O-H...O hydrogen-bonded networks and pi-pi interactions.