Crystal structure of the tris(1,10-phenanthroline)nickel aqua(ethylenediaminetetraacetato)bariate crystal hydrate [Ni(Phen)3][Ba(Edta)(H2O)]•12H2O

The crystal structure of [Ni(Phen)(3)][Ba(Edta)(H2O)] . 12H(2)O (I) was determined by X-ray diffraction analysis. The crystals are triclinic: a = 13.709(4) Angstrom, b 14.253(4) Angstrom, c = 1.4.806(2) Angstrom, alpha = 85.74(2)degrees, beta = 85.62(2)degrees, gamma = 69.55(1)degrees, Z= 2, space group P (1) over bar (direct methods, lambdaMoK(alpha), graphite monochromator, the H atoms of H2O were determined from difference Fourier syntheses, the other H atoms were located geometrically, anisotropic or isotropic (for hydrogen) least-squares method, R1 = 0.0353, wR2 = 0.0884, GOOF = 1.056). The unit cell contains [Ni(Phen)(3)](2+) cations, the [Ba-2(mu-Edta)(2)(H2O)(2)](4-) anions, and crystal water molecules. The barium coordination number is 8, the coordination polyhedron is a tetragonal antiprism. The Ni-N bond lengths in the cation are 2.077-2.104 Angstrom, the bond lengths in the anion are as follows: Ba-N 2.906 and 2.937 Angstrom; Ba-O (Edta) 2.708-2.772; Ba-O(w) 2.765 Angstrom. The crystal packing of structural units and the role of H2O molecules are analyzed. The structures of Group II metal compounds containing the Edta(4-) ligand are compared.