10.1007/s11173-008-2009-5

Abstract

The three title complexes, NH4[HoIII(Edta)(H2O)3] · 1.5H2O (I) (H4Edta = ethylenedianine-N,N,N′,N′-tetraacetic acid), (NH4)4[Ho III2 (Dtpa)2] · 9H2O (II) (H5Dtpa = diethylenetriamine-N,N,N′,N″,N″-entaacetic acid), and (NH4)3[HoIII(Ttha)] · 5H2O (III) (H6 Ttha = triethylenetetramine-N,N,N′,N″,N‴,N‴-hexaacetic acid), have been prepared and characterized by FT-IR, elemental analyses, and single-crystal X-ray diffraction technique. Complex I has a nine-coordinate mononuclear structure with distorted monocapped square antiprismatic conformation and its crystal structure belongs to orthorhombic system and Fdd2 space group. The crystal data are as follows: a = 19.343(9), b = 35.125(17), c = 12.364(6) Å, V = 8400(7) Å3, Z = 16, M = 552.26, ρcalcd = 1.747 g cm−3 μ = 3.828 mm−1, and F(000) = 4368. Complex II has a binuclear nine-coordinate pseudomonocapped square antiprismatic conformation and its crystal structure belongs to triclinic system and space P1 group. The crystal data are as follows: a = 9.7637(16), b = 9.9722(16), c = 12.945(2) Å, α= 85.853(2)°, β = 77. 140(2)°, γ = 77.140(2)°, V = 1198.4(3) Å3, Z = 1, M = 1340.80, ρcalcd = 1.858 g cm−3, μ = 3.380 mm−1, and F(000) = 674. As for complex III, it also has nine-coordinate mononuclear structure with distorted tricapped trigonal prism and its crystal structure belongs to monoclinic system andP21/c space group. The crystal data are as follows: a = 10.349(3), b = 12.760(4), c = 23.142(7) Å, β = 91.020(6)°, V = 3055.6(16) Å3, Z = 2, M = 797.55, ρcalcd = 1.734 g cm−3, μ = 2.674 mm−1, and F(000) = 1624. The results showed that although the ligands are different from one another in the shape and the numbers of coordination atoms, they all have nine-coordinate structures. However, one of them has binuclear structure and the other two have mononuclear structures because of the difference of the ligands.