metal-organic compounds
The rigid organic ligand (pyridine-3,5-diyl)diphosphonic acid has been used to create the title novel three-dimensional coordination polymer, [Ca(C5H6NO6P2)2(H2O)]n. The six-coordinate calcium ion is in a distorted octahedral environment, formed by five phosphonate O atoms from five different (pyridin-1-ium-3,5-diyl)diphosphonate ligands, two of which are unique, and one water O atom. Two crystallographically independent acid monoanions, L1 and L2, serve to link metal centres using two different coordination modes, viz. η2μ2 and η3μ3, respectively. The latter ligand, L2, forms a strongly undulated two-dimensional framework parallel to the crystallographic bc plane, whereas the former ligand, L1, is utilized in the formation of one-dimensional helical chains in the [010] direction. The two sublattices of L1 and L2 interweave at the Ca2+ ions to form a three-dimensional framework. In addition, multiple O—HO and N—HO hydrogen bonds stabilize the three-dimensional coordination network. Topologically, the three-dimensional framework can be simplified as a very unusual (2,3,5)-connected three-nodal net represented by the Schläfli symbol (4·82)(4·88·10)(8).
metal-organic compounds
The rigid organic linkers N-(4-bromophenylsulfonyl)dithiocarbimate(2−) and N-(4-iodophenylsulfonyl)dithiocarbimate(2−) crystallize with two potassium cations and two water molecules in their asymmetric units, forming the title coordination polymers, [K2(C7H4BrNO2S3)(H2O)2]n and [K2(C7H4INO2S3)(H2O)2]n. The anions and the water molecules link the potassium cations into broad two-dimensional networks, which are further linked by Khalide interactions.
organic compounds
The asymmetric unit of the title compound, 3C10H12N22+·2C10H11N2+·8C6H5NO5P−, contains one and a half naphthalene-1,5-diaminium cations, in which the half-molecule has inversion symmetry, one 5-aminonaphthalen-1-aminium cation and four hydrogen (5-carboxypyridin-3-yl)phosphonate anions. The crystal structure is layered and consists of hydrogen-bonded anionic monolayers between which the cations are arranged. The acid monoanions are organized into one-dimensional chains along the [101] direction via hydrogen bonds established between the phosphonate sites. (C)O—HNpy hydrogen bonds (py is pyridine) crosslink the chains to form an undulating (010) monolayer. The cations serve both to balance the charge of the anionic network and to connect neighbouring layers via multiple hydrogen bonds to form a three-dimensional supramolecular architecture.