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1.
Tetrafluoroaurates(III) of Lanthanoides M2F[AuF4]5 (M = Tb, Dy, Ho, Er) Tetrafluoroaurates(III) M2F[AuF4]5 with M = Tb, Dy, Ho, Er, all yellow, have been obtained. From single crystal data they crystallize triclinic, space group P1 -C1i (No. 2) with Tb: a = 1 194,34(7) pm, b = 798,46(6) pm, c = 902,02(7) pm, α = 89,033(7)°, β = 88,990(6)°, γ = 89,006(7)°; Dy: a = 1 191,66(9) pm, b = 796,33(8) pm, c = 899,65(9) pm, α = 88,956(8)°, β = 89,056(8)°, γ = 88,972(8)°; Ho: a = 1 189,06(10) pm, b = 795,46(6) pm, c = 896,81(7) pm, α = 88,912(8)°, β = 89,101(7)°, γ = 88,873(8)°; Er: a = 1 185,20(40), b = 793,98(14), c = 893,83(20), α = 88,751(23)°, β = 89,187(26)°, γ = 88,884(9)°  相似文献   

2.
Single crystals of lanthanide iodates have been quickly grown by decomposition of the corresponding periodates under hydrothermal conditions. Single crystal X‐ray diffraction showed that two structure types form with the elements from Pr‐Yb, an anhydrous form for Pr, Nd, Sm, Eu, Gd, Tb, Ho, Er and a dihydrate for Eu, Gd, Dy, Er, Tm, Yb. A detailed structure study is presented for one representative of each of these types, along with structure type and lattice parameters for the other materials. Tb(IO3)3: Space group P21/c, Z = 4, lattice dimensions at 120 K: a = 7.102(1), b = 8.468(1), c = 13.355(2)Å, β = 99.67(1)°; R1 = 0.034. Yb(IO3)3 · 2H2O: Space group P1¯, Z = 2, lattice dimensions at 120 K: a = 7.013(1), b = 7.370(1), c = 10.458(2)Å, α = 95.250(5), β = 105.096(5), γ = 109.910(10)°; R1 = 0.024.  相似文献   

3.
Synthesis and Crystal Structures of Lanthanide Bromide Thiosilicates Ln3Br[SiS4]2 (Ln = La, Ce, Pr, Nd, Sm, Gd) Single crystals of the bromide—thiosilicates Ln3Br[SiS4]2 were prepared by reaction of lanthanide metal (Ln = La, Ce, Pr, Nd, Sm, Gd), sulfur, silicon and bromine in quartz glass tubes. The thiosilicates crystallize in the monoclinic spacegroup C2/c (Z = 4) isotypically to the iodide analogues Ln3I(SiS4)2 and the A—type chloride—oxosilicates Ln3Cl[SiO4]2 with the following lattice constants: La3Br[SiS4]2: a = 1583.3(4) pm, b = 783.0(1) pm, c = 1098.2(3) pm, β = 97.33(3)° Ce3Br[SiS4]2: a = 1570.4(3) pm, b = 776.5(2) pm, c = 1092.2(2) pm, β = 97.28(2)° Pr3Br[SiS4]2: a = 1562.6(3) pm, b = 770.1(2) pm, c = 1088.9(2) pm, β = 97.50(2)° Nd3Br[SiS4]2: a = 1561.4(4) pm, b = 766.0(1) pm, c = 1085.3(2) pm, β = 97.66(3)° Sm3Br[SiS4]2: a = 1555.4(3) pm, b = 758.5(2) pm, c = 1079.9(2) pm, β = 98.28(2)° Gd3Br[SiS4]2: a = 1556.5(3) pm, b = 750.8(1) pm, c = 1074.5(2) pm, β = 99.26(2)° In the crystal structures the bromide ions form chains along [001] with trigonal planar coordination by lanthanide cations, while the [SiS4]4‐—building units display isolated distorted tetrahedra.  相似文献   

4.
Synthesis and Constitution of Fluorothalenite‐Type (Y3F[Si3O10]) Fluoride catena‐ Trisilicates M3F[Si3O10] with the Lanthanides (M = Dy, Ho, Er) By the reaction of the sesquioxides M2O3 with the corresponding trifluorides MF3 (M = Dy, Ho, Er), SiO2 and CsCl as flux (molar ratio: 1 : 1 : 3 : 6; 700 °C, 7 d) in evacuated silica tubes and gastight sealed metal capsules made of platinum, niobium or tantalum, respectively, single crystals of the fluoride silicates M3F[Si3O10] (monoclinic, P21/n; Z = 4; M = Dy: a = 734.06(6), b = 1116.55(9), c = 1040.62(8) pm, β = 97.281(7)°; M = Ho: a = 730.91(6), b = 1111.68(9), c = 1037.83(8) pm, β = 97.238(7)°; M = Er: a = 727.89(6), b = 1107.02(9), c = 1035.21(8) pm, β = 97.209(7)°) were obtained. The most important building groups in the crystal structures of the thalenite type are “isolated” [FM3]8+ triangles and catena‐trisilicate anions [Si3O10]8–, which contain three [SiO4] tetrahedra linked to a chain fragment via common corners. This has the shape of a horseshoe where both the terminal tetrahedra show different conformations (eclipsed and staggered) relative to the central unit. Therefore a chelatizing coordination on the same M3+ cation via oxygen atoms of both terminal [SiO4] groups is possible. The narrow area of existence of these fluoride silicates within the lanthanide series will be discussed and structural comparisons with other catena‐trisilicates are presented.  相似文献   

5.
本文利用非等温DSC曲线对十二种镧系元素异硫氰酸盐与苄胺形成的配合物Ln(NCS)3·4C6H5CH2NH2(Ln=La、Pr、Nd、Sm、Eu、Ge、Tb、Dy、Ho、Er、Tm、Yb)进行了非等温动力学研究, 并运用积分法和微分法进行了分析, 推断了它们的热分解反应机理函数。  相似文献   

6.
New Complexes of the Lanthanoides with Bidentate Ligands. The Crystal Structures of [(C17H17N2)GdBr2(thf)2] and [(C17H17N2)3Ln] (L = Sm, Gd) Reaction of [(AIP)Li] with GdBr3 leads to a new mononuclear complex [(AIP)GdBr2(thf)2] 1 . In contrast to this with SmI2 the compound [(AIP)3Sm] 2 is build up. Such complexes are also formed with Gd(OR*)3 (R* = OtBu2C6H3) and [(AIP)Li] in a 1:3 ratio, [(AIP)3Gd] 3 . The structures of 1–3 were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (No. 33), Z = 4, a = 1 972.7(9) pm, b = 984.7(5) pm, c = 1 425.0(8) pm, α = β = γ = 90°; 2 · 2 THF: space group C2/c (No. 15), Z = 8, a = 3 644.4(9) pm, b = 1 437.5(5) pm, c = 2 334.4(7) pm, β = 1 21.07(6)°; 3 : space group P2(1)/c (No. 14), Z = 4, a = 1 872.9(1) pm, b = 1 064.6(1) pm, c = 2 282.4(2) pm, β = 103.75(8)°).  相似文献   

7.
合成了13种1,5-双(1′-苯基-3′-甲基-5′-吡唑啉酮-4′)-戊二酮-[1,5](BPMPPD)和溴化十六烷基吡啶盐(CPB)的稀土配合物.研究了配合物的红外光谱、紫外可见光谱、差热-热重谱、荧光光谱、核磁共振谱及摩尔电导等性质,发现配合物属离子型缔合物CP+[Ln(BPMPPD)2]-.Pr、Nd、Ho、Er、Tm配合物发生超灵敏跃迁.配合物的热分解温度具有"四分组"效应,Sm、Eu、Tb、Oy为线性荧光。  相似文献   

8.
使用复杂晶体化学键理论计算了La0.5R0.5Ba2Cu3O7(R=Pr,Nd,Sm,Eu,Gd,Dy,Y,Ho,Er,Tm,Yb,Lu)(La-R123),Pr0.5R0.5Ba2Cu3O7(R=La,Nd,Sm,Eu,Gd,Dy,Ho,Y,Er,Tm,Yb,Lu)(Pr-R123)以及RBa2Cu3O7(R=La,Pr,Nd,Sm,Eu,Gd,Dy,Ho,Y,Er,Tm)(R123)中Cu-O键的键共价性,结果表明Pr-R123,La-R123,以及R123都应具有超导性,而实验结果是La0.5Pr0.5Ba2Cu07,R0.5,Pr0.5Ba2Cu3O7(R=La,Nd,Sm,Eu,Gd)无超导性,产生这种矛盾的原因尚不明确,需要做进一步的研究。  相似文献   

9.
-Lanthanide(III) chlorosulphates, Ln(SO3Cl)3 (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er) have been synthesized by solvolytic reaction of chlorosulphuric acid on the corresponding benzoates. The low conductivity values and the IR spectra of these compounds suggest a cation-anion interaction leading to covalent bonding. The bands observed in the reflectance spectra and the values of magnetic moments may indicate a coordination number of 6 for these metals, with bidentate chlorosulphate groups.  相似文献   

10.
Just O  Rees WS 《Inorganic chemistry》2001,40(8):1751-1755
Anhydrous lanthanide(III) chlorides (Ln = Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) react with 3 equiv of lithium 2,2,5,5-tetramethyl-2,5-disila-1-azacyclopentanide, Li[N[Si(CH3)2CH2Ch2Si(CH3)2]], in THF or Et(2)O to afford the monomeric four-coordinate heteroleptic ate complexes Ln[N[Si(CH3)2CH2CH2Si(CH3)2]]3(mu-Cl)Li(THF/Et2O)3 (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5), Ho (6), Er (7), Tm (8), Yb (9)), whose solid-state structures were determined by the single-crystal X-ray diffraction technique. All complexes additionally were characterized by melting point determination, elemental analyses, and mass spectrometry.  相似文献   

11.
Dynamic differential calorimetry has been employed to evaluate the heats of formation, heats and entropies of fusion of REPb3 compounds, where RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb. The results obtained have been estimated to be correct to within ±5–6‰ The general trend is a decrease in the heat of formation from La to Tm, which is correlated with the magnitude of the lanthanide contraction in these compounds.  相似文献   

12.
Interfacial distribution of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y between aqueous solutions of their salts and solutions of functionalized ionic liquid, 1,11-bis(1-methylimidazol-3-yl)-3,6,9-trioxaundecane bis(hexafluorophosphate) has been studied. The stoichiometry of extracted complexes has been determined, the effect of HNO3 concentration in aqueous phase on the efficiency of rare earth elements(III) recovery into organic phase has been considered.  相似文献   

13.
On Ordered Perovskites with Cationic Vacancies. IX. Compounds of the Type Sr2Sr1/4B □1/4WO6?Sr8SrB ?W4O24 (BIII ? La, Pr, Nd, Sm–Tm, Y) The compounds Sr2Sr1/4B□1/4WO6?Sr8SrB?W4O24 belong to the group of perovskites with octahedral cationic vacancies (cation/vacancy ratio (CN 6) ?:1). For the larger BIII ions (La, Pr, Nd, Sm–Dy) different ordering effects are observed. The perovskites with BIII ? Sm, Eu, Gd are polymorphic too (HT modification: higher ordered cubic perovskite (BIII ? Gd: a = 2X8.234 Å); LT modification: hexagonal perovskite stacking polytype (BIII ? Gd: a = 9.954 Å; c = 19.04 Å)). With the smaller BIII ions (Ho, Er, Tm and Y) a cubic, 1:1 ordered perovskite type is observed.  相似文献   

14.
The dissociation constants of 7-iodo-8-quinolinol-5-sulfonic acid and the formation constants of it's chelates with La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III) and Lu(III) have been determined potentiometrically in 1:1 v/v dioxane-water medium at 25±0.1°C and at an ionic strength of 1 with respect to sodium chloride.  相似文献   

15.
16.
The enthalpy of solution of Eu in Al and the standard molar enthalpy of formation of LnAl2 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) were determined by dissolution calorimetry, using a calorimeter based on liquid aluminium. Experimental results are compared with model predictions.  相似文献   

17.
New Results in the Chemistry of Lanthanoide Complexes. The Crystal Structures of [(C11H21N2)2LnBr] (Ln = Sm, Gd) LnBr3 leads with [(iPr2AIP)Li] (AIP = 2-iPropylamino-4-iPropylimino-2-Pentene) to the mononuclear complex [(iPr2AIP)2LnBr] (Ln = Gd 1 , Sm = 2 ). The structures of 1 – 2 were characterized by X-ray single crystal structure analysis.
  • 1: Space group Cc, Z = 4, a = 1283.3(7) pm, b = 1558.6(8) pm, c = 1330.1(7) pm, β = 90.24(4)°
  • 2: Space group Cc, Z = 4, a = 1281.7(2) pm, b = 1562.3(3) pm, c = 1329.8(2) pm, β = 90.09(1)°.
The Ln-Ion is coordinated by a Brom-Atom and the four Nitrogen-Atoms of the chelate ligand.  相似文献   

18.
The synthesis, characterization and tg-dsc study of Ln(tfa)3?·?3aza where Ln?=?La, Pr, Nd, Sm, Eu, Gd, Tb and Er, tfa?=?trifluoroacetate and aza?=?2-azacyclononanone are reported. The obtained X-ray powder diffraction patterns show that the compounds are divided in two isomorphous groups: La, Pr, Nd and Eu, Sm, Gd, Tb and Er. For all compounds, the thermodegradation under nitrogen gave the respective oxifluorides (LnOF) as the final product. The melting temperature intervals are 105–110°C, 100–112°C, 90–95°C, 79–101°C, 65–70°C, 75–90°C, 64–76°C and 50–65°C for the La, Pr, Nd, Sm, Eu, Gd, Tb and Er compounds, respectively, and it is verified that the lanthanide contraction induces a weaker intermolecular interaction between adjacent molecules in the solid state.  相似文献   

19.
The synthesis process and crystal structure evolution for a family of stoichiometric layered rare-earth hydroxides with general formula Ln(8)(OH)(20)Cl(4) x nH(2)O (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Y; n approximately 6-7) are described. Synthesis was accomplished through homogeneous precipitation of LnCl(3) x xH(2)O with hexamethylenetetramine to yield a single-phase product for Sm-Er and Y. Some minor coexisting phases were observed for Nd(3+) and Tm(3+), indicating a size limit for this layered series. Light lanthanides (Nd, Sm, Eu) crystallized into rectangular platelets, whereas platelets of heavy lanthanides from Gd tended to be of quasi-hexagonal morphology. Rietveld profile analysis revealed that all phases were isostructural in an orthorhombic layered structure featuring a positively charged layer, [Ln(8)(OH)(20)(H(2)O)(n)](4+), and interlayer charge-balancing Cl(-) ions. In-plane lattice parameters a and b decreased nearly linearly with a decrease in the rare-earth cation size. The interlamellar distance, c, was almost constant (approximately 8.70 A) for rare-earth elements Nd(3+), Sm(3+), and Eu(3+), but it suddenly decreased to approximately 8.45 A for Tb(3+), Dy(3+), Ho(3+), and Er(3+), which can be ascribed to two different degrees of hydration. Nd(3+) typically adopted a phase with high hydration, whereas a low-hydration phase was preferred for Tb(3+), Dy(3+), Ho(3+), Er(3+), and Tm(3+). Sm(3+), Eu(3+), and Gd(3+) samples were sensitive to humidity conditions because high- and low-hydration phases were interconvertible at a critical humidity of 10%, 20%, and 50%, respectively, as supported by both X-ray diffraction and gravimetry as a function of the relative humidity. In the phase conversion process, interlayer expansion or contraction of approximately 0.2 A also occurred as a possible consequence of absorption/desorption of H(2)O molecules. The hydration difference was also evidenced by refinement results. The number of coordinated water molecules per formula weight, n, changed from 6.6 for the high-hydration Gd sample to 6.0 for the low-hydration Gd sample. Also, the hydration number usually decreased with increasing atomic number; e.g., n = 7.4, 6.3, 7.2, and 6.6 for high-hydration Nd, Sm, Eu, and Gd, and n = 6.0, 5.8, 5.6, 5.4, and 4.9 for low-hydration Gd, Tb, Dy, Ho, and Er. The variation in the average Ln-O bond length with decreasing size of the lanthanide ions is also discussed. This family of layered lanthanide compounds highlights a novel chemistry of interplay between crystal structure stability and coordination geometry with water molecules.  相似文献   

20.
Nine new A2Mo4Sb2O18 (A=Ce, Pr, Eu, Tb, Ho, Er, Tm, Yb, Lu) compounds have been synthesized by solid-state reactions. They are isostructural with six reported analogues of yttrium and other lanthanides and the monoclinic unit cell parameters of all fifteen of them vary linearly with the size of A3+ ion. Single crystal X-ray structures of eight A2Mo4Sb2O18 (A=Ce, Pr, Eu, Gd, Tb, Ho, Er, Tm) compounds have been determined. Neat A2Mo4Sb2O18 (A=Pr, Sm, Eu, Tb, Dy, Ho, Er, Tm) compounds exhibit characteristic rare earth metal photoluminescence.  相似文献   

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