Mononuclear eight-coordinate (NH₄)₃[Y^III(Nta)₂] and one-dimensional unlimited zigzag type nine-coordinate {K[Y^III(Egta) · 4H₂O}_n complexes: Syntheses and structural determination

The title complexes (NH4)(3)[Y-III(Nta)(2)] (I) (H(3)Nta = nitrilotriacetic acid) and {K[Y-III(Egta)] center dot 4H(2)O}(n) (II) (H(4)Egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid) were prepared, and their molecular and crystal structures were determined by single-crystal X-ray diffraction techniques. Complex I crystallizes in the rhombohedral crystal system with R (3) over barc space group. The central Y3+ ion is eight-coordinated by two nitrogen and six oxygen atoms, which come from two tetradentate Nta ligands. The crystal data are as follows: a = 7.9340(14)angstrom, c = 54.611(15)angstrom, V = 2977.1(11)angstrom(3), Z = 6, p(calcd) = 1.738 mg/cm(3), mu = 3.011 mm(-1), F(000) = 1596, R = 0.0234 and wR = 0.0641 for 686 observed reflections with I >= 2 sigma(I). The {K[Y-III(Egta)] center dot 4H(2)O}(n) is nine- coordinated by two nitrogen and seven oxygen atoms and produces a 1D unlimited zigzag-type chain through a bridging carboxylic group. {K[Y-III(Egta)] center dot 4H(2)O}(n) crystallizes in the monoclinic crystal system with C2/c space group. The crystal data are as follows: a = 37.588(5)angstrom, b = 13.7101(19)angstrom, c = 8.6070(12)angstrom, beta = 99.929(2)degrees, V = 4369.0(11)angstrom(3), Z = 8, p(calcd) = 1.753 mg/cm(3), mu = 2.934 mm(-1), F(000) = 2368, R = 0.0385 and wR = 0.0800 for 4082 observed reflections with I >= 2 sigma(I).