A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows th...A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered guest water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure.展开更多
A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 47...A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 473 and 1.880 in poly crys talline powder at room temperature is quite different from the U spectrum. The c oordination number of Gd 3+ is nine with a monocapped square antiprism geom etry. And the stacking effect was observed in the complex. The crystal of the co mplex belongs to triclinic with space group P 1, a=0.9626(4) n m, b=0.9732(4) nm, c=1.1758(5) nm, α=102.45(1)°, β=108.16(1) °, γ=96.68(2)°, V=1.0018(7) nm3, Z=2, D c=1.80 g·cm -3 , μ(MoKα)=33.63 mm -1, F(000)=530, GOF=1.80, R=0.023 and R w=0.027.展开更多
The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterize...The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterized by elemental analysis,thermal analysis,IR spectra and single-crystal X-ray structure analysis.The crystal of the Gd(Ⅲ) complex belongs to triclinic system,space group P1 with:a=0.796 25(16) nm,b=0.944 46(19) nm,c=1.262 1(3) nm,α=76.50(3)°,β=84.95(3)°,γ=83.04(3)°,Z=2,V=0.914 4(3) nm3,Dc=2.669 g.cm-1,μ=7.269 mm-1,F(000)=692,and R1=0.033 3,wR2=0.062 3.The crystal structure revealed that compound 1 has a 2D layer structure incorporating 1D Gd-O-Gd double chain,and hydrogen bonding interactions result in the former of 3D supramolecular network structure.CCDC:669079.展开更多
EPR spectra of three new quaternary gadolinium complexes(I: [Gd(C6H5COO)2(NO3)(bipy)]2,Ⅱ: [Gd(m- CH3C6H4COO)2(NO3)(phen)]2 andⅢ: [Gd(p- CH3C6H4COO)(NO3)(phen)]2) with mixed anion ligands in polycrystalline powder...EPR spectra of three new quaternary gadolinium complexes(I: [Gd(C6H5COO)2(NO3)(bipy)]2,Ⅱ: [Gd(m- CH3C6H4COO)2(NO3)(phen)]2 andⅢ: [Gd(p- CH3C6H4COO)(NO3)(phen)]2) with mixed anion ligands in polycrystalline powders and solutions have been investigated at different temperatures and solvents.New behavior of EPR spectra of complexⅢ was first observed in polycrystalline powder at 77K and three types of EPR spectra for three complexes,symmetry resonance spectrum for the complexⅡ ,U spectrum for the complexⅢ ,and asymmetry resonance spectrum for the complex I.The relationship of EPR features between the crystal- field strength in the complexes and local symmetry around Gd(Ⅲ ) was discussed.The crystal- field parameters b20 and asymmetry parametersλ′ of the complexes I andⅢ were estimated.展开更多
基金supported by the National Natural Science Foundation of China(No.20471056)
文摘A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered guest water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure.
文摘A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 473 and 1.880 in poly crys talline powder at room temperature is quite different from the U spectrum. The c oordination number of Gd 3+ is nine with a monocapped square antiprism geom etry. And the stacking effect was observed in the complex. The crystal of the co mplex belongs to triclinic with space group P 1, a=0.9626(4) n m, b=0.9732(4) nm, c=1.1758(5) nm, α=102.45(1)°, β=108.16(1) °, γ=96.68(2)°, V=1.0018(7) nm3, Z=2, D c=1.80 g·cm -3 , μ(MoKα)=33.63 mm -1, F(000)=530, GOF=1.80, R=0.023 and R w=0.027.
文摘The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterized by elemental analysis,thermal analysis,IR spectra and single-crystal X-ray structure analysis.The crystal of the Gd(Ⅲ) complex belongs to triclinic system,space group P1 with:a=0.796 25(16) nm,b=0.944 46(19) nm,c=1.262 1(3) nm,α=76.50(3)°,β=84.95(3)°,γ=83.04(3)°,Z=2,V=0.914 4(3) nm3,Dc=2.669 g.cm-1,μ=7.269 mm-1,F(000)=692,and R1=0.033 3,wR2=0.062 3.The crystal structure revealed that compound 1 has a 2D layer structure incorporating 1D Gd-O-Gd double chain,and hydrogen bonding interactions result in the former of 3D supramolecular network structure.CCDC:669079.
文摘EPR spectra of three new quaternary gadolinium complexes(I: [Gd(C6H5COO)2(NO3)(bipy)]2,Ⅱ: [Gd(m- CH3C6H4COO)2(NO3)(phen)]2 andⅢ: [Gd(p- CH3C6H4COO)(NO3)(phen)]2) with mixed anion ligands in polycrystalline powders and solutions have been investigated at different temperatures and solvents.New behavior of EPR spectra of complexⅢ was first observed in polycrystalline powder at 77K and three types of EPR spectra for three complexes,symmetry resonance spectrum for the complexⅡ ,U spectrum for the complexⅢ ,and asymmetry resonance spectrum for the complex I.The relationship of EPR features between the crystal- field strength in the complexes and local symmetry around Gd(Ⅲ ) was discussed.The crystal- field parameters b20 and asymmetry parametersλ′ of the complexes I andⅢ were estimated.