RESUMO
In the asymmetric unit of the title compound, catena-poly[[diaqua-magnesium(II)]-µ-oxalato], [Mg(C(2)O(4))(H(2)O)(2)](n), there is one Mg atom in an octa-hedral coordination with site symmetry 222, a unique C atom of the oxalate anion lying on a twofold axis, an O atom of the anion in a general position and a water O atom at a site with imposed twofold rotation symmetry. The Mg(2+) ions are ligated by water mol-ecules and bridged by the anions to form chains that are held together by O-Hâ¯O hydrogen bonds. The structure of the title compound has already been reported in a different space group [Lagier, Pezerat & Dubernat (1969 â¶). Rev. Chim. Miner.6, 1081-1093; Levy, Perrotey & Visser (1971 â¶). Bull. Soc. Chim. Fr. pp. 757-761].
RESUMO
The title compound, {Na(2)[Mg(2)(C(2)O(4))(3)(H(2)O)(2)]}(n), is isotypic with its Co analogue. There are two crystallographically independent oxalate groups in the asymmetric unit, one lying on an inversion center and the other on a general position. Mg(2+) ions are ligated by H(2)O mol-ecules and bridged by tri- and tetra-dentate oxalate ligands, forming ladder-like double chains that are held together via O-Hâ¯O hydrogen bonds, with Na(+) cations located between the chains to balance the charge.
RESUMO
The title compound represents a new structure type, in which distorted VO6 octahedra are bridged by iodate groups to form infinite two-dimensional [VO2(IO3)2]- layers that are separated by octahedrally coordinated Li+ cations.
RESUMO
The crystal structure of Ce(IO3)3 consists of one-dimensional chains of edge-sharing CeO9 polyhedra which are crosslinked into two-dimensional layers through bridging IO3- groups. The layers are held together via long I...O contacts, resulting in an extended three-dimensional network. The I-O bond distances and O-I-O angles are normal, lying in the ranges 1.806 (4)-1.846 (4) A and 89.9 (2)-100.9 (2) degrees, respectively. The three crystallographically independent iodate groups all show different coordination modes.
RESUMO
Ga(IO(3))(3) crystallizes in the space group P6(3), with the Ga atom at a site with imposed threefold symmetry. The crystal structure consists of slightly distorted GaO(6) octahedra that are bridged by I atoms of IO(3)(-) groups, giving rise to a three-dimensional polar network. The framework contains unoccupied hexagonal channels running parallel to the hexagonal [001] direction. The iodate groups have their stereochemically active non-bonded electron pairs pointing in the same direction along [001], which creates the polarity in the structure. The I-O bond distances and O-I-O angles are normal, being in the ranges 1.783 (3)-1.847 (2) A and 94.68 (11)-99.61 (12) degrees , respectively.