metal-organic compounds
Open access
In the title compound, {(NH4)[Ag(C5HN2O6)2(H2O)]}n, the AgI cation is seven-coordinated and is surrounded by four oxo O atoms of the 2,3,5,6-tetraoxo-4-nitropyridin-4-ide species [Ag—O = 2.3848 (19), 2.4931 (18), 2.5361 (18) and 2.573 (2) Å], two nitro O atoms [Ag—O = 2.644 (2) and 2.661 (2) Å], and one water molecule [Ag—O = 2.3133 (19) Å]. The pyridin-4-ide mono-anions act as polydentate bridging ligands and form a three-dimensional network that is stabilized through O—HO and N—HO hydrogen bonds involving the coordinating water molecule and the imide function as donator groups. The ammonium cations are located in the cavities of the framework and are also involved in hydrogen bonding to O atoms of the ligand.
metal-organic compounds
Open access
In the title compound, [Ba(C7H5N2O5)2(H2O)6]·4H2O, the Ba2+ cation lies on a twofold rotation axis and is ten-coordinated by two 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide oxo O atoms [Ba—O = 2.8715 (17) Å], two hydroxyimino N atoms [Ba—N = 3.036 (2) Å], and six water molecules [Ba—O = 2.847 (2), 2.848 (2), and 2.880 (2) Å]. The 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide monoanions act in a bidentate chelating manner, coordinating through an N atom of the non-deprotonated hydroxyimino group and an O atom of the neighboring oxo group. Two lattice water molecules are located in the cavities of the framework and are involved in hydrogen bonding to O atoms of one of the coordinating water molecules and the O atom of a keto group of the ligand. As a result, a three-dimensional network is formed.