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The crystal structure of the title compound, {[Zn(C6H3N2O4)(H2O)2]NO3}n, is built of zigzag cationic chains propagating in [010] with nitrate anions located in the space between the chains. The ZnII ion is coordinated by N and O atoms of two symmetry-related ligands in equatorial sites, and by two water O atoms at the axial sites of a distorted octahedron. One carboxylate group of the ligand remains protonated, serving as a donor in a short intramolecular O—H
O hydrogen bond. The coordinated water molecules are donors and the nitrate O atoms act as acceptors in a network of O—HO hydrogen bonds.
O hydrogen bond. The coordinated water molecules are donors and the nitrate O atoms act as acceptors in a network of O—HO hydrogen bonds.metal-organic compoundsOpen access
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The unit cell of the title compound, (N2H5)2[Li2(C6H2N2O4)2(H2O)2]·[Li4(C6H2N2O4)2(H2O)8], comprises two centrosymmetric complexes, one double negatively charged and one neutral, and two mono-protonated hydrazine cations. The anionic complex molecule is a dimer, built of a pair of symmetry-related pyridazine-3,6-dicarboxylate ligands and a pair of LiI ions, each coordinated by two N,O-chelating sites donated by a ligand molecule and an aqua O atom at the apical position. The pentacoordination around the LiI ions is partway between a trigonal–bipyramidal and a square-pyramidal arrangement. The two carboxylic acid groups of the ligand are deprotonated and one carboxylate O atom of each group is not involved in the coordination, and this applies to both the anionic and the neutral complex. The neutral complex molecule is also composed of a pair of LiI ions and a pair of ligand molecules related by a centre of symmetry. They form a dimeric core in which the pentacoordination of the LiI ions includes two N,O-bonding groups donated by two ligands and an aqua O atom. The pentacoordination is described as partway between a trigonal–bipyramidal and a square-pyramidal arrangement. The coordinated carboxylate group is bidentate–bridging, forming with an Li(H2O)3 unit a neutral tetrameric molecule. The coordination of the tetracoordinated LiI ion shows a slightly distorted tetrahedral geometry. An extended system of O—HO and N—HO hydrogen bonds contributes to the stability of the crystal structure.
O and N—HO hydrogen bonds contributes to the stability of the crystal structure.metal-organic compoundsOpen access
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The structure of the title compound, {(N2H5)[Li3(C6H2N2O4)2(H2O)2]·H2O}n, is composed of molecular dimers, each built up of two symmetry-related LiI ions with distorted trigonal–bipyramidal coordinations bridged by two deprotonated ligand molecules via their N,O-bonding sites. Doubly solvated LiI ions with a distorted tetrahedral geometry link adjacent dimers, forming a polymer generated by bridging bidentate carboxylato O atoms to LiI ions in adjacent dimers, forming anionic layers parallel to the ac plane with monoprotonated hydrazinium cations and crystal water molecules positioned between them. The layers are held together by an extended system of hydrogen bonds in which the hydrazinium cations and coordinated and crystal water molecules act as donors and carboxylate O atoms act as acceptors.
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The title compound, [Mg(C5H3N2O4)2(H2O)2], consists of centrosymmetric neutral monomers in which two O,O′-bidentate imidazolinium-4,5-dicarboxylate ligands are bonded to the MgII ion. One of the carboxyl protons is transferred to the N atom of the imidazole ring. The octahedral metal-ion coordination is completed by two trans water O atoms. In the crystal, molecules are linked by N—H(O,O) and O—HO hydrogen bonds.
(O,O) and O—HO hydrogen bonds.metal-organic compoundsOpen access
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The asymmetric unit of the polymeric title compound, [Mg3(C9H3O6)2(C3H7NO)4]n, contains three MgII ions bridged by carboxylate O atoms from two fully deprotonated benzene-1,3,5-tricarboxylate (BTC) trianions and four metal-coordinated dimethylformamide (DMF) molecules. One MgII ion is octahedrally coordinated by six carboxylate O atoms. The other two cations are each octahedrally coordinated by four carboxylate O atoms and two O atoms donated by two DMF molecules: in one, the DMF molecules are cis and in the other they are trans. The three MgII octahedra form clusters, which are bridged by the BTC trianions, generating a three-dimensional structure.
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The structure of the title compound, [Li(C5H3N2O2)(H2O)]n, contains an LiI ion with a distorted trigonal–bipyramidal coordination environment involving the N and O atoms of pyrazine-2-carboxylate ligands with a bridging carboxylate group, and two aqua O atoms also in a bridging mode. The symmetry-related LiI ions bridged by a carboxylate O atom and a coordinating water O atom form an Li2O2 unit with an LiLi distance of 3.052 (4) Å, which generates molecular ribbons propagating in the c-axis direction. The ribbons are held together by a network of O—HO hydrogen bonds in which the coordinating water molecules act as donors and the carboxylate O atoms as acceptors.
Li distance of 3.052 (4) Å, which generates molecular ribbons propagating in the c-axis direction. The ribbons are held together by a network of O—HO hydrogen bonds in which the coordinating water molecules act as donors and the carboxylate O atoms as acceptors.metal-organic compoundsOpen access
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The asymmetric unit of the title compound, [Li4(C5H3N2O2)4(H2O)4], contains two symmetry-independent LiI ions, two symmetry-independent ligands and two symmetry-independent coordinated water molecules. They form a dinuclear unit in which the two LiI ions are bridged by two carboxylate O atoms from the two ligands. Two dinuclear units related by an inversion centre form the tetrameric molecule. One of the LiI ions shows a distorted tetrahedral coordination geometry, the other a distorted trigonal–bipyramidal environment. The tetramers are held together by hydrogen bonds in which coordinated water molecules act as donors, and the carboxylate O atoms act as acceptors. A hydrogen bond between coordinated water molecule as donor and a ring N atom as acceptor is also observed.
metal-organic compoundsOpen access
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The asymmetric unit of the title compound, [Li4(C6H2N2O4)2(H2O)6]n, comprises two Li+ ions bridged by a completely deprotonated pyrimidine-3,6-dicarboxylate ligand and coordinated by two water molecules; the asymmetric units related by an inversion operation create a structural unit which forms part of a two-dimensional polymeric structure parallel to (10-1). One of the Li+ ions shows a distorted tetrahedral arrangement involving two symmetry-related coordinating water molecules and two carboxylate O atoms. The other Li+ ion is in distorted trigonal–bipyramidal geometry defined by N and O atoms of the ligands and a water molecule. Water O atoms are proton donors to carboxylate O atoms forming hydrogen bonds.
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The asymmetric unit of the title compound, [Li4(C5H3N2O2)2(H2O)5]Cl2, contains two LiI cations, one with a distorted trigonal–bipyramidal and the other with a distorted tetrahedral coordination geometry. Two symmetry-related asymmetric units constitute a building block of the structure, in which both ligand carboxylate O atoms are bidentate and bridge the metal ions, forming a divalent cation. Charge balance is maintained by two chloride anions. The building blocks, bridged by LiI cations, form cationic ribbons with chloride anions in the space between them. The ribbons propagate in [010] and are held together by a network of weak O—HO hydrogen bonds which operate in the space between adjacent ribbons.
O hydrogen bonds which operate in the space between adjacent ribbons. metal-organic compoundsOpen access
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The polymeric structure of the title compound, {[Ca2(C6H2N2O4)2(H2O)6]·2H2O}n, is built up of molecular layers composed of CaII ions bridged by both ligand N and O atoms with one of the O atoms being bis-monodentate. Two adjacent CaII ions are bridged by these O atoms, forming a centrosymmetric dimer which is the building unit of the structure. The dimers are nodes of a cross-linked molecular layer parallel to (101). The CaII ion is coordinated by two bidentate ligands, one monodentate ligand and three water molecules in the form of a distorted polyhedron with a coordination number of eight. Solvate water molecules located between adjacent layers participate as donors and acceptors in a system of hydrogen bonds in which coordinating water molecules also act as donors and non-coordinating carboxylate O atoms act as acceptors.
