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1.
Two novel 3-D coordination compounds, Nd2[C6(COO)6](H2O)6 (1)and Ho2[C6(COO)6](H2O)6 (2), were hydrothermaily synthesized from mellitic acid and neodymium perchlorate (or holmium perchlorate) in the alkaline aqueous solution and characterized with elemental analysis, TG, IR spectrum, and single crystal X-ray diffraction. The two compounds were isostructural and crystallized in the orthorhombic system, space group Pnnm, with a=1.3531 (4) nm, b=0.6687 (2) nm, c=1.0224(3) nm, V=0.92523(5) nm^3, Z=4, D=2.630 g/cm^3, F(000)=696.0, Goof=1.052. Final R indices [1 〉2∑(Ⅰ)]: R1=0.0195, wR2=0.0382 for 1; a=1.3411 (2) nm, b=0.6586(1) nm, c=1.0116(2) nm, V=0.8935(3) nm^3, Z=4, D=2.877 g/cm^3, F(000)=724.0, Goof=1.061. Final R indices [1 〉2∑(Ⅰ)]: R1=0.0200, wR2=0.0479 for 2. In the two compounds 1 and 2, the mellitic acid ligand, in which all the carboxylate groups were deprotonated, had only one kind of coordination mode to bridge metal ions to form four-connected three-dimensional diamondiod networks.  相似文献   

2.
Two novel 3-D coordination compounds, Nd2[C6(COO)6](H2O)6 (1) and Ho2[C6(COO)6](H2O)6 (2), were hydrothermally synthe-sized from mellitic acid and neodymium perchlorate (or holmium perchlorate) in the alkaline aqueous solution and characterized with ele-mental analysis, TG, IR spectrum, and single crystal X-ray diffraction. The two compounds were isostructural and crystallized in the ortho-rhombic system, space group Pnnm, with a=1.3531 (4) nm, b=0.6687 (2) nm, c=1.0224(3) nm, V=0.92523(5) nm3, Z=4, D=2.630 g/cm3, F(000)=696.0, Goof=1.052. Final R indices [I >2Σ(I)]: R1=0.0195, wR2=0.0382 for 1; a=1.3411(2) nm, b=0.6586(1) nm, c=1.0116(2) nm, V=0.8935(3) nm3, Z=4, D=2.877 g/cm3, F(000)=724.0, Goof=1.061. Final R indices [I >2Σ(I)]: R1=0.0200, wR2=0.0479 for 2. In the two compounds 1 and 2, the mellitic acid ligand, in which all the carboxylate groups were deprotonated, had only one kind of coordination mode to bridge metal ions to form four-connected three-dimensional diamondiod networks.  相似文献   

3.
Recently ,therehasbeenconsiderablein terestinlanthanide(Ⅲ )hexacyanoferratesandtheanalogouscobalt(Ⅲ )aswellaschromium(Ⅲ )complexesbecauseoftheirpotentialascatalytic ,semiconductive ,andmagneticmate rials[1~ 4] .Forexample ,magneticstudiesonaseriesofthree dimensio…  相似文献   

4.
Inthepastfewyears ,themagneticprop ertiesofcomplexescomprisinglanthanideandtransitionmetalionshaveattractedincreasinginterest[1~ 6 ] .Thesecomplexesareimportantinthestudiesofmagneticexchangeinteractionbetweenlanthanideandd transitionmetalions,andtheycanpro…  相似文献   

5.
6.
Reaction of (C5Me4SiMe3)Y(CH2SiMe)2(THF) with two equivalents of iPrN=C=NiPr in hexane at room temperature afforded a mixed-ligand yttrium complex (C5Me4SiMe3)[(iPrN)2CCH2SiMe3]2Y. X-ray diffraction revealed that the center metal was nine-coordinated by one cyclopentadienyl ring and two amidinate ligands, and adopted a four-legged piano stool geometry.  相似文献   

7.
A new complex Eu2(PA)6(phen)2 was prepared with hydrothermal reaction using EuCl3.6H2O, phenylmalonic acid (H2phma), and 1, 10-phenanthroline (phen), where PA was the decarboxylated product of HEphma, phenylacetate. The crystal structure of the title complex was determined with the X-ray diffraction. The title complex was a binuclear molecule with an inversion center. Each Eu^3+ ion was nine-coordinated with two nitrogen atoms from one phen molecule and seven oxygen atoms from five PA ligands. The carboxylic groups were bonded to the Eu^3+ ion in three modes, the chelating bidentate, the bridging bidentate, and the bridging-chelating tridentate. The complex emits intense red fluorescence under ultraviolet light. The luminescence peaks correspond to the characteristic emission 5D0→7FJ (J=0-4) transitions of the Eu^3+ ion.  相似文献   

8.
YW2O6(OH)3:Tb3+ green phosphors were synthesized at different pH values via a facile hydrothermal method. The structure and optical properties of as-synthesized samples were studied by X-ray diffractometer (XRD), scanning electron microscopy (SEM), photolumi-nescence spectra and luminescence decay curve. The results showed that pure monoclinic YW2O6(OH)3:Tb3+ green phosphors could be ob-tained at pH 2-5. Uniform spherical micro-phosphors of ~5 μm in diameter with narrow size distribution could be prepared at pH 5. pH value had dramatic influence on morphologies, which could be ascribed to the various spatial configurations of different poly-tungstates existing at different pH values. The emission spectra under 261 nm excitation exhibited dominant green emission at 546 nm. The green emission inten-sity reached the maximum value at pH 5 due to the high packing density of the obtained phosphor.  相似文献   

9.
A new dimeric lanthanum(Ⅲ) complex [La2(phen)2(C7H3N2O6)6](phen=1,10-phenanthroline) was synthesized by the hydrothermal method and determined by single crystal X-ray diffraction analysis. The La(Ⅲ) ion is coordinated to seven oxygen atoms from five carboxylate groups and two nitrogen atoms from a phen ligand,forming a monocapped square antiprismatic geometry. Six carboxylate groups coordinate to two La(Ⅲ) ions in three modes which are chelating bidentate,bridging bidentate and bridging tridentate. The crystal is triclinic with space group P-1,a=1.2030(4) nm,b=1.2962(5) nm,c=1.3330(5) nm,α=104.410(5)°,β=114.048(4)°,γ=100.054(4)°,V=1.7467(10) nm3,Mr=952.46,Z=2,Dc=1.811 g·cm-3,F(000)=944,S=1.017,μ=1.320 mm-1,with R1=0.0298 and wR2=0.0625.  相似文献   

10.
A new polyoxometalate dimer based on lacunary Wells-Dawson anion and lanthanide cation, Na14[{Nd(H2O)3 (α2-PeWt7O61)2]·17H2O, was isolated as a sodium salt under ambient conditions and characterized by IR, TG, and X-ray single crystal structure analysis and electrochemistry. It belonged to the triclinic, space group Pi with a=1.26738 (15) nm, b=1.41464 (17) nm, c=2.3254 (4) nm, α=103.142 (2)°, β = 95.122 (2)°, γ=113.9690 (10)°, V=3.6317 (8)nm^3, Z=2, Dc=4.274 mg/m^3, and μ=27.695 mm^-1. The Nd^3+ ion was substituted for a [W=O]^4+ unit in the "cap" site of the tungsten-oxygen framework of the parent Wells-Dawson ion. The cyclic voltammograms of the title compound exhibited nearly chemically reversible one-step one-electron transfer process and two-step irreversible reduction processes. Thermogravimetric showed a one-step slow weight loss stage in the range of 25-850 ℃.  相似文献   

11.
Two complexes [Eu2(2-TFMBA)6(2,2′-bipy)2]·2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2′-bipy=2,2′-bipyridine; 1,10-phen= 1,10-phenanthroline) were synthesized by solvent method and determined by X-ray diffraction analysis. Complex 1 crystallizes in monoclinic system with space group P21/c, whereas complex 2 crystallizes in triclinic system with space group Pi. Both are binuclear molecules with an inversion center. In complex 1, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in bidentate-bridging mode. Each Eu^3+ ion is eight-coordinated with six O atoms from five 2-TFMBA ligands and two N atoms from one 2,2′-bipy molecule. In complex 2, two center Eu^3+ ions are linked together by four 2-TFMBA ligands in two modes, namely, bidentate-bridging and tridentate-bridging. Each Eu^3+ ion is nine-coordinated with seven O atoms from five 2-TFMBA ligands and two N atoms from one 1,10-phen molecule. The two complexes both exhibited strong red fluorescence under ultraviolet light, and the ^5D0→^7Fj (j=0-4) transition emissions of Eu^3+ ion were observed in their emission spectra.  相似文献   

12.
A new complex of lanthanum orotate [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was synthesized using a hydrothermal method. The crystal structure was determined with help of single crystal X-ray diffraction analysis. The complex crystallized in orthorhombic system, Cmc2(1) space group. In the complex, the center lanthanum (Ⅲ) ion was nine-coordinated with coordination geometry of a distorted monocapped square antiprism, in which two of the nine coordinated oxygen atoms were from two orotate ligands in a monodentate mode, one oxygen atom from a hydroxyl, and the others from six coordinated water molecules. The mononuclear complex [La(C5H3N2O4)2(OH)(H2O)6 ]·2(C5H4N2O4)·9H2O was linked through the hydrogen bonds into an infinite supermolecular honeycomb structure.  相似文献   

13.
刘睦清  高忆慈 《稀土》2006,27(5):15-19
合成了2,3-二氯异丁酸根和4-甲基吡啶氮氧化物稀土三元配合物(RE=La、Ce、Pr、Nd、Sm、Eu).通过元素分析、红外、紫外、荧光、X射线粉末衍射、XPS、热分析以及摩尔电导等分析手段,确定了配合物的组成为[REL3(4-picNO)H2O](L= CH3C2H2Cl2COO -),并对它们的性质进行了讨论.  相似文献   

14.
A new chain europium complex [Eu(2,3-DFBA)3·(H2O)2]n(2,3-DFBA=2,3-difluorobenzoate) was synthesized by solvent method.X-ray single-crystal diffraction analysis revealed that Eu3+ ions were linked through 2,3-DFBA groups via alternate bidentate-bridging and tridentate chelating-bridging coordination modes to form a one-dimensional(1-D) polymeric chain.Each Eu3+ ion is eight-coordinated by six O atoms of five 2,3-DFBA ligands and two water molecules.The abundant hydrogen bonds between chains resulted in a two...  相似文献   

15.
Reaction of Na2CO3, Pr6O11 and H3PO4 gave the sodium praseodymium polyphosphate NaPr(PO3)4. The title compound crystallized in the monoclinic P21/n space group with a=0.9965(4) nm, b=1.31437(4) nm, c=0.72271(3) nm,β=90.429(3)°, V=0.9465(4) nm3, Z=4, R=0.0493 and wR=0.1266 for 1855 independent reflections. The structure of NaPr(PO3)4 consisted of PrO8 polyhedra sharing oxygen atoms with phosphoric group PO4 to form a three-dimensional framework, delimiting intersecting tunnels in which the sodium ion was located. Each Na+ ion was bonded to seven oxygen atoms.  相似文献   

16.
Crystalengineeringofcoordinationpoly merswithopenframeworksassembledfromor ganic metalcompoundshasbeenofgreatinter estsowingtotheirpotentialpropertiesasnovelmaterialssuchasgasadsorption[1,2 ] ,ion ex change[3] andcatalysis[4] .Theconstructionofcoordinationpolym…  相似文献   

17.
The crystal structure of a novel Eu3 coordination polymer, {[Eu(m-BDC)(NO3)(Phen)(H2O)]2 · 2CH3CH2OH}n (m-BDC=1,3-benzenedicarboxylate, Phen=1, 10-phenanthroline), was obtained and its high-resolution luminescence spectra at 77K were measured. The μ2-carboxylate of m-BDC constructs the binuclear building block in which each Eu3 ion is coordinated by four oxygen atoms of m-BDC anions, one oxygen atom from water molecule, two oxygen atoms of nitrate and two nitrogen atoms of Phen, respectively. The μ1-carboxylate of m-BDC conjugates the binuclear units one-dimensional chain or a ribbon, while the hydrogen bonds between ribbons assemble the structure two-dimensional layer with a thickness equaling to the width of the ribbon. The luminescence spectra reveal that the two Eu3 ion sites in the binuclear building blocks have slight environmental difference. The C1 local symmetry of Eu3 ion is concluded from both crystal structure measurement and luminescence spectra.  相似文献   

18.
李增和  朱玉俊  柳正文 《稀土》2007,28(5):72-76
采用水热法合成稀土无机有机杂化化合物[Nd(PW11O39)(H2O)3 ](H2bpy)2·4H2O.采用NdCl3·6H2O,(NH4)3PW12O40·3H2O, 4,4'-联吡啶(bpy),和去离子水(摩尔比为4∶1∶4∶3900, pH=6)在130℃下进行水热反应3天,得到标题化合物的紫红色块状晶体,并进行了红外光谱分析,元素分析.用单晶X射线衍射法测得晶体结构,属三斜晶系,空间群为P-1,晶胞参数为a=1.18824(9) nm,b =1.35707(10)nm,c=1.77691(13)nm,α=71.551(2)°,β=82.478(2)°,γ=80.568(2)°.该晶体由无机的共价链∞1[Nd(PW11O39)(H2O)3]4- 和有机的二质子化的4,4'-联吡啶(H2bpy)2 及结晶水分子堆积而成的, 是一个新的稀土磷钨酸盐无机有机杂化化合物.  相似文献   

19.
Polymeric cerium nitrate complex with 1,4-bis (phenylsulfinyl) butane (bphsb) [Ce(bphsb)2(NO3)3]n (1) was synthesized and characterized. The crystal structure of the complex indicated that the ligand bphsb and cerium( Ⅲ ) ion form a polymeric double-bridge chain complex involving 18-membered macrometallocycles. Each cerium ion is coordinated by ten 0 atoms in a distorted 4,4-bicapped square antiprism. In the complex the disulfoxide ligand acts as bis-monodentate O-ligand bridging metal centers.  相似文献   

20.
Two dinuclear compounds [Ln2(acetate)6(H2O)4]-4H2O (Ln=Tb(1), Sm(2)) were obtained by the hydrothermal reaction of Ln2O3 with malonic acid at 150 ℃. Both compounds were characterized by elemental analyses, infrared spectra, and single crystal X-ray diffraction. The results showed that complexes 1 and 2 were isomorphous and crystallize in triclinic space group P 1. The coordination geometry around Ln(Ⅲ) ions in the complexes 1 and 2 was a distorted tricapped trigonal prism with a nine coordination. In the crystal, the molecular organization was further stabilized by well-defined weak hydrogen bonding interactions between the neutral dinuclear molecular units that led to the formation of a three-dimensional network. The fluorescence properties of the two complexes 1 and 2 in organic solvents were also studied. The results show that the ligand acetate favored energy transfer to the emitting energy level of Tb(Ⅲ) in complex 1. Some factors that influence the fluorescent intensity were also discussed in the article.  相似文献   

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