Syntheses,structural determination,and binding studies of binuclear nine-coordinate (MnH)4[Ho 2 III (Dtpa)2] · 12H2O and polynuclear nine-coordinate {(MnH)[HoIII(Egta)] · 3H2O} n

Two novel rare earth metal coordination compounds, (MnH)₄[Ho ^III₂ (Dtpa)₂] · 12H₂O (I) (Mn = methylamine, H₅Dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaaceticacid) and {(MnH)[Ho^III(Egta)] · 3H₂O} _n (II) (H₄Egta = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) have been successfully synthesized through direct heating reflux and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction techniques (CIF files CCDC nos. 890878 (I) and 1457061 (II)). Complex I shapes a binuclear nine-coordinate structure with distorted tricapped trigonal prismatic conformation and crystallizes in the triclinic crystal system with space group P1?. The central Ho³⁺ ion is coordinated by three nitrogens and six oxygens from two octadentate Dtpa ligands. The cell dimensions are as follows: a = 9.8420(10), b = 12.1319(13), c = 13.2931(15) Å, α = 89.223(2)°, β = 68.4280(10)°, γ = 72.1280(10)° and V = 1396.0(3) ų. Complex II adopts a polynuclear nine-coordinate structure with pseudo-monocapped square antiprismatic conformation and crystallizes in the monoclinic crystal system with space group C2/c. The central Ho³⁺ ion is coordinated by two nitrogens and seven oxygens from two octadentate Egta ligands. The crystal data are as follows: a = 38.4755(13), b =13.5569(5), c = 8.7343(3) Å, β = 100.135(3)° and V = 4484.8(3) ų.

     

Syntheses and structural determination of binuclear nine-coordinate (NH4)4[SmIII2(Httha)2]·16H2O and 2-D ladder-like binuclear nine-coordinate (NH4)4[SmIII2(dtpa)2]·10H2O

Two rare-earth metal coordination compounds, (NH₄)₄[Sm^III₂(Httha)₂]·16H₂O (1) (H₆ttha?=?triethylenetetramine-N,N,N′,N′′,N′′′,N′′′-hexaacetic acid) and (NH₄)₄[Sm^III₂(dtpa)₂]·10H₂O (2) (H₅dtpa?=?diethylenetriamine-N,N,N′,N′′,N′′-pentaacetic acid), have been synthesized through reflux and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction techniques. Sm^III of (NH₄)₄[Sm^III₂(Httha)₂]·16H₂O (1) is nine-coordinate, forming tricapped trigonal prismatic coordination with three amine nitrogens and six oxygens, in which four oxygens are from one ttha and two from the other ttha. (NH₄)₄[Sm^III₂(Httha)₂]·16H₂O (1) crystallizes in the monoclinic crystal system with P2(1)/c space group. The crystal data are: a?=?13.9340(13) Å, b?=?22.890(3) Å, c?=?20.708(2) (14) Å, β?=?99.521(2)°, and V?=?6513.7(13) ų. There are two –NH⁺– groups in the [Sm^III₂(Httha)₂]^4?. The polymeric (NH₄)₄[Sm^III₂(dtpa)₂]·10H₂O (2) also is nine-coordinate with tricapped trigonal prismatic conformation and crystallizes in the triclinic crystal system with P–1 space group. The cell dimensions are: a?=?9.8240(8) Å, b?=?10.0329(9) Å, c?=?13.0941(11) Å, β?=?77.1640(10)°, and V?=?1227.30(18) ų. In (NH₄)₄[Sm^III₂(dtpa)₂]·10H₂O, there are two types of ammonium cations, which connect [Sm^III₂(dtpa)₂]^4? and lattice water through hydrogen bonds, leading to a 2-D ladder-like layer structure.     

Syntheses,structural determination,and binding studies of binuclear eight-coordinate (enH2)[GdIII 2(pdta)2(H2O)2] · 8H2O and mononuclear nine-coordinate (enH2)[GdIII(egta)(H2O)]2 · 6H2O

The (enH₂)[Gd^III ₂(pdta)₂(H₂O)₂]?·?8H₂O (1) (en?=?ethylenediamine and H₄pdta?=?propylenediamine-N,?N,?N′,?N′-tetraacetic acid) and (enH₂)[Gd^III(egta)(H₂O)]₂?·?6H₂O (2) (H₄egta?=?ethyleneglycol-bis-(2-aminoethylether)-N,?N,?N′,?N′-tetraacetic acid) complexes were synthesized and characterized by infrared spectrum, thermal analysis, and single-crystal X-ray diffraction. The complex (enH₂)[Gd^III ₂(pdta)₂(H₂O)₂]?·?8H₂O has a binuclear eight-coordinate structure with pseudo square antiprism and crystallizes in the monoclinic crystal system with C2/c space group. Through a carboxylate bridge, an infinite 1-D zigzag polymeric binuclear [Gd^III ₂(pdta)₂(H₂O)₂]^2? complex anion is formed. All infinite zigzag polymeric complex anions link through hydrogen bonds, yielding a layer structure. (enH₂)[Gd^III(egta)(H₂O)]₂?·?6H₂O has a mononuclear nine-coordinate structure with pseudo monocapped square antiprism and crystallizes in the monoclinic crystal system with P2₁/n space group. Each enH₂ ²⁺ cation, through hydrogen bonds, connects two adjacent [Gd^III(egta)(H₂O)]^? complex anions.     

Syntheses, spectroscopic analysis, and structural determination of two novel nine-coordinate mononuclear Na4[EuIII(Dtpa)(H2O)]2 · 11.5H2O and binuclear (NH4)4[EuIII(Dtpa)]2 · 10H2O complexes

Two novel rare-earth metal complexes, namely, mononuclear Na₄[Eu^III(Dtpa)(H₂O)]₂ · 11.5H₂O (I) and binuciear (NH₄)₄[Eu^III(Dtpa)]₂ · 10H₂O (II) (H₅Dtpa = diethylenetriamine-N,N,N??,N??,N??-pentaacetic acid), have successfully been synthesized and characterized by infrared spectrum, UV-Vis spectrum, fluorescence spectrum, thermal analysis, and single-crystal X-ray diffraction techniques. Since these two Eu(III) complexes have different counterions, causing different coordination environment, fluorescence spectrum analysis displays different fluorescence properties. X-ray diffraction reveals that the coordination polyhedra of both complexes adopt pseudo-D _3h tricapped trigonal prismatic conformation. However, I is a nine-coordinate mononuclear complex and crystallizes in the monoclinic crystal space group P2₁/n and II is a nine-coordinate binuciear complex and crystallizes in the triclinic crystal space group $P\bar 1$ . In addition, II has two independent binuciear structural units, [Eu(1)₂(Dtpa)₂] and [Eu(2)₂(Dtpa)₂]. Along the yz plane both [Eu(1)₂(Dtpa)₂] and [Eu(2)₂(Dtpa)₂] form a 1D chain structure, respectively. Further, along the y axis linking of each other forms a 2D planar structure.     

Syntheses and structural determination of the nine-coordinate rare earth metal complexes: [TbIII(Eg3a)(H2O)2] · 4.5H2O and K[TbIII(Edta)(H2O)3] · 5H2O

Two title complexes, [Tb^III(Eg3a)(H₂O)₂] · 4.5H₂O (I) (H₃Eg3a = 3-carboxymethyl-6, 9-dioxa-3,12-diazatetradecanedioic acid) and K[Tb^III(Edta)(H₂O)₃] · 5H₂O(II) (H₄Edta = ethylenediamine-N,N,N′,N′-tetraaceti acid), were prepared and characterized by FT-IR, elemental analyses, TGA-DTA-DTG, and single-crystal X-ray diffraction technique. For I, the Tb³⁺ ion is nine-coordinated by an Eg3a ligand and two coordination water molecules, yielding a monocapped square-antiprismatic (MCSAP) conformation. Complex I crystallizes in the monoclinic system with P2₁/c space group. The crystal data are as follows: a = 9.237(3), b = 10.018(3), c = 23.580(7) Å, β = 99.021(5)°, V = 2155.2(11) ų, Z = 4, ρ = 1.822 Mg m^?3, μ = 3.353 mm^?1, F(000) = 1180, R ₁ = 0.0445 and wR ₂ = 0.1034 for 4262 observed reflections with I ≥ 2σ(I). For II, the Tb³⁺ ion is nine-coordinated by an Edta ligand and three coordinate water molecules also yielding a MCSAP conformation. Complex II crystallizes in the orthorhombic system with Fdd2 space group. The crystal data are as follows: a = 19.373(5), b = 35.429(10), c = 12.114(3) Å, V = 8315(4) ų, Z = 16, ρ = 2.014 Mg m^?3, μ = 2.014 mm^?1, F(000) = 5024, R ₁ = 0.0224 and wR ₂ = 0.0557 for 3189 observed reflections with I ≥ 2σ(I). The potassium cations bridge the coordination spheres yielding many infinite long 1-D zigzag-type chains. The molecular structure of I is more stable than that of II. According to thermal analyses, the collapsing temperatures of crystal structure are 314°C for I and 348°C for II, which indicates that the crystal structure of II is more stable.     

Syntheses,structural determination,and binding studies of nine-coordinate multinuclear (mnH)2[EuIII(egta)]2·6H2O and binuclear (mnH)4[EuIII2(dtpa)2]·6H2O

Two lanthanide complexes, (mnH)₂[Eu^III(egta)]₂·6H₂O (1) (H₄egta = ethyleneglycol-bis-(2aminoethylether)-N,N,N′,N′-tetraacetic acid) and (mnH)₄[Eu^III₂(dtpa)₂]·6H₂O (2) (H₅dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaacetic acid), have been synthesized and characterized by FT-IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction reveals that 1 is multinuclear nine-coordinate and crystallizes in the monoclinic crystal system with space group C2/c. The obtained cell dimensions are a = 38.513(3)?Å, b = 13.5877(8)?Å, c = 8.7051(5)?Å, β = 99.6780(10)°, and 4490.6(5)?ų. Each methylamine (mnH⁺) cation in 1, through hydrogen bonds, connects three adjacent [Eu^III(egta)]^? anions. The [Eu^III(egta)]^? anions connect one another forming a 1-D multinuclear zigzag chain structure along the c-axis. Complex 2 is nine-coordinate binuclear structure with tricapped trigonal prismatic conformation and crystallizing in the monoclinic crystal system, but with space group P2₁/n. The obtained cell dimensions are a = 9.9132(8)?Å, b = 24.1027(18)?Å, c = 10.7120(10)?Å, β = 109.1220(10)°, and 2418.2(3)?ų. For 2, there are two kinds of methylamine cations (mnH⁺) connecting [Eu^III₂(dtpa)₂]^4? complex anions and lattice waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure.     

Syntheses and structures of mononuclear eight-coordinate Na[ErIII(Cydta)(H2O2]·5H2O (Cydta = trans-1,2-cyclohexanediaminetetraacetic acid) and binuclear nine-coordinate Na2[SmIII(Cydta)][SmIII(Cydta)(H2O)3] · 11H2O

The title complexes, Na[Er^III(Cydta)(H₂O)₂] · 5H₂O (I) and Na₂[Sm^III(Cydta)][Sm^III(Cydta)(H₂O)₃] · 11H₂O (II) (Cydta is trans-1,2-cyclohexanediaminetetraacetic acid), are prepared and characterized using IR, elemental analyses, and single-crystal X-ray diffraction techniques. Crystal I belongs to triclinic system (space group P1), which has a mononuclear eight-coordinate slightly distorted square antiprismatic conformation. The crystal data are as follows: a = 8.371(12) Å, b = 9.952(14) Å, c = 14.74(2) Å, α = 88.32(2)°, β = 76.30(2)°, γ = 87.87(2)°, V = 1192(3) ų, Z = 1, ρ = 1.835 g/cm³, μ = 3.612 mm^?1, F(000) = 658, R = 0.0194, and wR = 0.0520 for 4130 observed reflections with I≥2σ(I). Crystal II belongs to monoclinic system (space group P2₁/n), which has the binuclear nine-coordinate structure with tricapped trigonal prismatic conformation for Sm(1) and the pseudomonocapped square antiprismatic conformation for Sm(2). The crystal data are as follows: a = 12.283(6) Å, b = 15.626(7) Å, c = 25.875(12) Å, β = 97.962(7)°, V = 4919(4) ų, Z = 4, ρ = 1.717 g/cm³, μ = 2.476 mm^?1, F(000) = 2536, R = 0.0781, and wR = 0.1745 for 8554 observed reflections with I ≥ 2σ(I).     

Syntheses, structural determination, and binding studies of mononuclear nine-coordinate (EnH2)1.5[HoIII(Ttha)] · 4.5H2O and two dimensional unlimited network (EnH2)[HoIII(Egta)(H2O)]2 · 6H2O

Two novel complexes, (EnH₂)_1.5[Ho^III(Ttha)] · 4.5H₂O (I) (En = ethylenediamine and H₆Ttha = triethylenetetramine-N,N,N′,N″,N?,N?-hexaacetic acid) and (EnH₂)[Ho^III(Egta)(H₂O)]₂ · 6H₂O (II) (H₄Egta = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid), were synthesized and their crystal structures were determined by single crystal X-ray diffraction techniques. Complex I has a nine-coordinate mononuclear structure with distorted tricapped trigonal prismatic conformation and crystallizes in the monoclinic crystal system with P2/n space group. The crystal data are as follows: a = 17.7541(18), b = 9.6810(10), c = 22.166(2) Å, β = 118.913(2)°, and V = 3335.0(6) ų. Complex II has a mononuclear nine-coordinate structure with pseudo-monocapped square antiprismatic conformation and crystallizes in the monoclinic crystal system with P2₁/n space group. The crystal data are as follows: a = 12.978(8), b = 12.685(8), c = 14.905(9) Å, β = 105.333(7)°, and V = 2366(2) ų. In I, there are two types of EnH ₂ ²⁺ anions. They connect to [Ho^III(Ttha)]^3? by hydrogen bonds leading to the formation of 3D pore structure along z axis. In II, EnH ₂ ²⁺ cation connects three adjacent [Ho^III(Egta)(H₂O)]^? complex anions through hydrogen bonds, these hydrogen bonds lead to the formation of 2D network structure in [101] plane. The results showed that ligand structures play a crucial role in crystal and molecular structure of their complexes. In addition, the protonated (EnH ₂ ²⁺ ) cations conjugating to [Ho^III(Ttha)]^3? and [Ho^III(Egta)(H₂O)]^? complex anions are reviewed, which act as an important beginning for study of Ho(III) complexes conjugating with other various amino and heterocyclic biomolecule.     

Syntheses and structural determination of eight-coordinate Na[YbIII(Cydta)(H2O)2] · 5H2O and [YbIII(Hegta)] · 2H2O complexes

Na[Yb^III(Cydta)(H₂O)₂] · 5H₂O (1) (H₄Cydta = trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetic acid) and [Yb^III(Hegta)] · 2H₂O (2) (H₄egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) were prepared and their composition and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques. Complex 1 crystallized in the triclinic crystal system with space group P 1; the Yb^III is eight-coordinate by a hexadentate Cydta and two water molecules. Complex 2 is a protonated egta complex, crystallized in the monoclinic crystal system with space group P 2 ₁ /c; Yb^III is coordinated only by the octadentate Hegta ligand. Both these complexes adopt a pseudo-square antiprismatic conformation.     

Researches on crystal and molecular structures of nine-coordination mononuclear K[Eu III 2 (Edta)(H2O)3]·3.5H2O and binuclear K4[(HTtha)2]·13.5H2O

The crystal and molecular structures of the K[Eu^III(Edta)(H₂O)₃] 3.5H₂O (I) (H₄Edta = ethylenediaminetetraacetic acid) and K₄[Eu₂^III(HTtha)₂] 13.5H₂O (II) (H₆Ttha = triethylenetetraminehexaacetic acid) complexes have been determined by single-crystal X-ray diffraction analyses. The crystal of I belongs to orthorhombic crystal system and Fdd2 space group. The crystal data are as follows: a = 1.9849(6)nm, b = 3.5598(11)nm, c = 1.2222(4)nm, V = 8.636(5)nm³, Z = 16, M = 596.37, (calcd) = 1.835g/cm³, µ= 3.166mm^–1, and F (000) = 4752. The final R and wR values are 0.0269 and 0.0692 for 2936 (I > 2.0 (I)) reflections and 0.0317 and 0.0708 for all 7284 unique reflections, respectively. The [Eu^III(Edta)(H₂O)₃]^– complex anion has a nine-coordination pseudo-monocapped square antiprismatic structure in which the nine coordinated atom are two N and seven O atoms (four from one Edta ligand and three water molecules). The crystal of II belongs to monoclinic system and P2¹/n space group. The crystal data are as follows: a = 1.1337(3)nm, b = 2.5753(6)nm, c = 2.2138(6) nm, = 102.871(5)°, V = 6.301(3) nm³, Z = 4, M = 1682.33, (calcd) = 1.773g/cm³, = 2.339mm^–1, and F(000) = 3404. The final R and wR are 0.0514 and 0.0906 for 11144 (I> 2.0(I)) reflections and 0.0976 and 0.1068 for all 26 048 unique reflections, respectively. The whole complex molecule is composed of two close parts in which every one has a nine-coordination structure as a distorted monocapped square antiprism. The Ttha ligand in the [Eu ₂^III(HTtha)₂]^4– complex anion coordinates to one central Eu ³⁺ ion with three N atoms and four O atoms and to the other Eu³⁺ ion with two O atoms.From Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 901–909.Original English Text Copyright © 2004 by J. Wang, X. Zhang, Y. Zhang, Y. Wang, X. Liu, Z. Liu.This article was submitted by the authors in English.     

Syntheses and structures of nine-coordinate NH4[HoIII(Edta)(H2O)3] · 1.5H2O, (NH4)4[Ho 2 III (Dtpa)2] · 9H2O, and (NH4)3[HoIII(Ttha)] · 5H2O complexes

The three title complexes, NH₄[Ho^III(Edta)(H₂O)₃] · 1.5H₂O (I) (H₄Edta = ethylenedianine-N,N,N′,N′-tetraacetic acid), (NH₄)₄[Ho ₂ ^III (Dtpa)₂] · 9H₂O (II) (H₅Dtpa = diethylenetriamine-N,N,N′,N″,N″-entaacetic acid), and (NH₄)₃[Ho^III(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) ų, Z = 16, M = 552.26, ρ_calcd = 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) ų, Z = 1, M = 1340.80, ρ_calcd = 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) ų, Z = 2, M = 797.55, ρ_calcd = 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.     

Syntheses,structural determination,and binding studies of nine-coordinate mononuclear (mnH)2[DyIII(Httha)]·3H2O and (enH2)3[DyIII(ttha)]2·9H2O

Two dysprosium coordination compounds, (mnH)₂[Dy^III(Httha)]·3H₂O (1) (H₆ttha?=?triethylenetetramine-N,N,N′,N″,N′′′,N′′′-hexaacetic acid and mn?=?methylamine) and (enH₂)₃[Dy^III(ttha)]₂·9H₂O (2) (en?=?ethylenediamine), were synthesized through direct heating and characterized by elemental analysis, FT-IR, thermal analysis, and single-crystal X-ray diffraction. X-ray diffraction analysis displays that 1 is a mononuclear nine-coordinate complex with a pseudo-monocapped square antiprismatic conformation (MCSAP) crystallizing in the monoclinic crystal system with P2(1)/c space group. The crystal data are as follows: a?=?16.1363(19)?Å, b?=?13.9336(11)?Å, c?=?13.6619(14)?Å, β?=?102.2490(10)°, and V?=?3001.8(5)?ų. There are two kinds of methylamine cation in 1. They connect [Dy^III(Httha)]^2?and crystal waters through hydrogen bonds, leading to formation of a 2-D ladder-like layer structure. The polymeric 2 also is a nine-coordinate structure with a pseudo-MCSAP crystallizing in the monoclinic crystal system with P2/c space group. The cell dimensions are: a?=?17.7801(16)?Å, b?=?9.7035(10)?Å, c?=?22.096(2)?Å, β?=?118.874(2)°, and V?=?3338.3(6)?ų. In 2 there are also two types of ethylenediamine cations. One connects three adjacent [Dy^III(ttha)]^3? complex anions through hydrogen bonds and the other is symmetrical forming hydrogen bonds with two neighboring [Dy^III(ttha)]^3? complex anions. These hydrogen bonds result in formation of a 2-D ladder-like layer structure as well.     

Syntheses and structural determinations of the nine-coordinate rare earth metal: Na4[DyIII(dtpa)(H2O)]2·16H2O,Na[DyIII(edta)(H2O)3]·3.25H2O and Na3[DyIII(nta)2(H2O)]·5.5H2O

Three complexes, Na₄[Dy^III(dtpa)(H₂O)]₂?·?16H₂O, Na[Dy^III(edta)(H₂O)₃]?·?3.25H₂O and Na₃[Dy^III (nta)₂(H₂O)]?·?5.5H₂O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na₄[Dy^III(dtpa)(H₂O)]₂?·?16H₂O crystallizes in the monoclinic system with P2₁/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?ų, Z?=?4, M?=?1517.87?g?mol^?1, D _c?=?1.879?g?cm^?3, μ?=?2.914?mm^?1, F(000)?=?3032, and its structure is refined to R ₁(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[Dy^III(edta)(H₂O)₃]?·?3.25H₂O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?ų, Z?=?16, M?=?586.31?g?mol^?1, D _c?=?1.876?g?cm^?3, μ?=?3.690?mm^?1, F(000)?=?4632, and its structure is refined to R ₁(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na₃[Dy^III(nta)₂(H₂O)]?·?5.5H₂O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?ų, Z?=?8, M?=?724.81?g?mol^?1, D _c?=?2.102?g?cm^?3, μ?=?3.422?mm^?1, F(000)?=?2848, and its structure is refined to R ₁(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na₄[Dy^III(dtpa)(H₂O)]₂?·?16H₂O and Na₃[Dy^III(nta)₂(H₂O)]?·?5.5H₂O, but monocapped square antiprism for Na[Dy^III(edta)(H₂O)₃]?·?3.25H₂O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na₄[Dy^III(dtpa)(H₂O)]₂?·?16H₂O, 1-D zigzag type structure for Na[Dy^III(edta)(H₂O)₃]?·?3.25H₂O and a 2-D parallelogram for Na₃[Dy^III(nta)₂(H₂O)]?·?5.5H₂O. According to thermal analyses, the collapsing temperatures are 356°C for Na₄[Dy^III(dtpa)(H₂O)]₂?·?16H₂O, 371°C for Na[Dy^III(edta)(H₂O)₃]?·?3.25H₂O and 387°C for Na₃[Dy^III(nta)₂(H₂O)]?·?5.5H₂O, which indicates that their crystal structures are very stable.     

Syntheses and Structural Researches of Nine-Coordinated (NH4)[EuIII(Edta)(H2O)3] · H2O and (NH4)3[EuIII(Ttha)] · 5H2O1

The crystal and molecular structures of the (NH₄)[Eu^III(Edta)(H₂O)₃] · H₂O (I); Edta^4– is an ethylenediaminetetraacetate anion) and (NH₄)₃[Eu^III(Ttha)] · 5H₂O (II); Ttha^6– is a triethylenetetraminehexaacetate anion) complexes have been determined by single-crystal X-ray structure analysis. The crystal of complex I is orthorhombic with Fdd2 space group. The crystal data are as follows: a = 1.9505(8) nm, b = 3.5445(14) nm, c = 1.2442(5) nm, V = 8.602(6) nm³, Z = 16, M = 531.29, p = 1.579 g cm^–3, = 2.970 mm^–1, and F(OOO) = 3924. The final R and wR values are 0.0378 and 0.1030 for 2799 (I > 2.0(I)) unique reflections, and 0.0495 and 0.1072 for all 6237 reflections, respectively. The nine-coordinated [Eu^III(Edta)(H₂O)₃]^– complex anion has a pseudo-monocapped square antiprismatic structure in which the nine coordinated atoms, two N and four O are from one Edta ligand and three O atoms from water molecules. The crystal of complex II is monoclinic with P2₁/c space group. The crystal data are as follows: a = 1.0387(3) nm, b = 1.2737(4) nm, c = 2.3031(7) nm, = 90.870(5)°, V = 3.047(2) nm³, Z = 4, M = 784.58, C 51.83, H 4.32, N 115.12. = 1.710 g cm^–3, = 2.143 mm^–1 and F(000) = 1608. The final R and wR are 0.0400 and 0.0720 for 5909 (I > 2.0(I)) unique reflections, and 0.0747 and 0.0799 for all 13825 reflections, respectively. The nine-coordinated [Eu^III(Ttha)]^3– complex anion has a pseudo-monocapped square antiprismatic structure in which the Ttha acts as an ninedentate ligand with four N atoms of amino groups and five O atoms of carboxylic groups actually, in addition, there is a non-coordinated free carboxylic group in the structure.     

K3[GdⅢ(nta)2(H2O)]·6H2O和(NH4)·[GdⅢ(Cydta)(H2O)2]·5H2O的合成及晶体结构

GdⅢ的配合物常被用作MRI造影剂[1,2]. GdⅢ的离子半径和电子结构分别为0.107 8 nm和高自旋f 7, 理论预测应与氨基多羧酸类配体形成稳定的九配位配合物[3～5]. 为证实理论预测并在此基础上寻找合适的可用于定向修饰的配体以及为提高GdⅢ配合物的脂溶性使其具有更好的细胞渗透性, 选择四齿配体nta和含有脂环烃的六齿配体Cydta分别合成了GdⅢ的配合物, 并测定了它们的分子结构. 结果显示, GdⅢ与nta形成九配位配合物, GdⅢ与Cydta形成八配位配合物.     

Synthesis and Structure of a Novel Compound [Cu2(EDTA)(Py)2(H2O)2]·2H2O

A novel compound [Cu2(EDTA)(Py)2(H2O)2]·2H2O was synthesized by the reaction of CuSO4(5H2O with H4EDTA in pyridine/water (V/V = 1/4) solvent, and characterized by elemental analysis, IR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n with a = 1.26974(6), b = 0.67949(3), c = 1.48548(3) nm, β = 91.454(2)o, V = 1.28122(9) nm3, Z = 2, Dc = 1.673 g/cm3, Mr = 645.56, F(000) = 664, μ(MoKα) = 1.729 mm-1, the final R = 0.0353 and wR = 0.0832 for 1920 observed reflections (I > 2((I)). The compound is a centrosymmetric binuclear molecule with bridged EDTA group. Each Cu(II) atom is linked to two oxygen atoms and one nitrogen atom of EDTA, one oxygen atom of water and one nitrogen atom of pyridine to form a distorted square pyramidal environment. There exist face-to-face π-π stacking interactions between pyridine rings from neighboring molecule with the interplanar distance of 0.3670 nm and hydrogen bonding between EDTA and water molecules.     

Syntheses and crystal structures of two Cd(II) coordination polymers: one-dimensional chain [Cd(C4H6N2)2(C4H2O4)(H2O)2] n and two-dimensional sheet [Cd(C4H6N2)(H2O)(C4H4O4)] n · n H2O

Two new Cd(II) coordination polymers, [Cd(C₄H₆N₂)₂(C₄H₂O₄)(H₂O)₂] _n (1) (where C₄H₆N₂?=?2-methylimidazole, C₄H₂O₄?=?fumarate), and [Cd(C₄H₆N₂)(H₂O)(C₄H₄O₄)] _n ?·?nH₂O (2), (where C₄H₄O₄?=?succinates), have been prepared and structurally characterized by single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 in a one-dimensional chain structure, in which carboxy is monodentate; a three-dimensional supermolecular network structure was formed through hydrogen bonding. In complex 2, the coordination geometry of the Cd atoms is a pentagonal bipyramid, and a two-dimensional sheet is formed though carboxyl group bridging. In 1 and 2, IR spectra indicate the presence of bridging carboxyl groups, confirmed by structure analyses.