Poly[bis(μ-5-iodoisophthalato)(methanol)dilead(II)] exhibiting a novel centrosymmetric rhombus-shaped I4unit
The asymmetric unit of the title compound, [Pb2(C8H3IO4)2(CH4O)]n, contains two PbIIatoms, two 5-iodoisophthalate (5-IIP2−) ligands and one coordinated methanol molecule. One Pb atom is eight-coordinated, surrounded by seven carboxylate O atoms from five 5-IIP2−ligands and one O atom from the terminal methanol ligand. The other Pb atom is seven-coordinated in a hemidirected geometry, surrounded by seven carboxylate O atoms from five 5-IIP2−ligands. Both Pb atoms are connected by carboxylate groups to form a one-dimensional infinite rod along theaaxis; neighbouring rods are further linked by the aromatic rings of 5-IIP2−to generate the final three-dimensional structure with channels in theadirection. An O—H...O hydrogen bond between the methanol ligand and one of the carboxylate groups of a 5-IIP2−ligand stablizes the three-dimensional framework. Interestingly, a centrosymmetric rhombus-shaped I4unit is formed by four 5-IIP2−ligands, with I...I distances of 3.8841 (8) and 3.9204 (8) Å.