Experimental and theoretical structural investigation of an ionic Nd coordination polymer.

Research concerning coordination polymers has been intense due to their significant variability and structural stability. With this in mind, an ionic neodymium coordination polymer was synthesized, composed of an anionic one-dimensional polymer interconnected to a cationic three-dimensional porous polymer, poly[dodecaaquabis(μ-pyridine-4-carbohydrazide-κ²N:O)bis(μ₂-4-sulfobenzoato-κ²O:O')bis(μ₃-4-sulfobenzoato-κ³O:O':O'')trineodymium(III)] catena-poly[aquabis(μ-pyridine-4-carbohydrazide-κ²N:O)bis(μ₂-4-sulfobenzoato-κ²O:O')neodymium(III)] 4.33-hydrate, {[Nd₃(C₇H₄O₅S)₄(C₆H₇N₃O)₂(H₂O)₁₂][Nd(C₇H₄O₅S)₂(C₆H₇N₃O)₂(H₂O)]·4.33H₂O}_n. The ligands used were 4-sulfobenzoate (PSB) and pyridine-4-carbohydrazide, popularly known as isoniazid (INH), an antibiotic drug. The compound crystallizes in the monoclinic space group C2/c, with Z = 4. Solid-state calculations suggest that the crystal structure is mainly stabilized by hydrogen bonds, i.e. O-H...O and N-H...O interactions among the polymers, and by van der Waals interactions involving the organic side chains. This net is tetragonal, 2-nodal 3,4-connected, and can be described as the dmd (sqc 528) type.