The first example of solvothermally synthesized thioantimonates(V) with ethylenediamine coordinated lanthanide(III): [Sm(en)4]SbS4 x 0.5en and [Sm(en)3(H2O)(micro-SbS4)]infinity

Under mild solvothermal conditions two novel thioantimonates(V) [Sm(en)4]SbS4 x 0.5en (1) and [Sm(en)3(H2O)(micro-SbS4)]infinity (2) were synthesized; the structure of 1 contains discrete [Sm(en)4]3+ and [SbS4]3 ions, while 2 consists of neutral [Sm(en)3(H2O) (micro-SbS4)] one-dimensional chains.     

Crystal-chemical features of monoclinic lanthanide oxobromotungstates of composition LnWO4Br (Ln = Eu, Gd, Dy, Er, Yb)

The crystal-chemical properties of lanthanide oxobromotungstates of composition LnWO₄Br (Ln = Eu, Gd, Dy, Er, Yb) are studied. The crystal system and space group for the oxobromotungstates are determined. The unit cell parameters are refined. The parameters a, b, c, and V of the LnWO₄Br compounds are studied as functions of the atomic number of the lanthanide. Analytical equations are derived to predict unit cell parameters for unsynthesized lanthanide oxobromotungstates of the class in question.     

Luminescence tuning of imidazole-based lanthanide(III) complexes [Ln = Sm, Eu, Gd, Tb, Dy

To tune the lanthanide luminescence in related molecular structures, we synthesized and characterized a series of lanthanide complexes with imidazole-based ligands: two tripodal ligands, tris{[2-{(1-methylimidazol-2-yl)methylidene}amino]ethyl}amine (Me(3)L), and tris{[2-{(imidazol-4-yl)methylidene}amino]ethyl}amine (H(3)L), and the dipodal ligand bis{[2-{(imidazol-4-yl)methylidene}amino]ethyl}amine (H(2)L). The general formulas are [Ln(Me(3)L)(H(2)O)(2)](NO(3))(3)·3H(2)O (Ln = 3+ lanthanide ion: Sm (1), Eu (2), Gd (3), Tb (4), and Dy (5)), [Ln(H(3)L)(NO(3))](NO(3))(2)·MeOH (Ln(3+) = Sm (6), Eu (7), Gd (8), Tb (9), and Dy (10)), and [Ln(H(2)L)(NO(3))(2)(MeOH)](NO(3))·MeOH (Ln(3+) = Sm (11), Eu (12), Gd (13), Tb (14), and Dy (15)). Each lanthanide ion is 9-coordinate in the complexes with the Me(3)L and H(3)L ligands and 10-coordinate in the complexes with the H(2)L ligand, in which counter anion and solvent molecules are also coordinated. The complexes show a screw arrangement of ligands around the lanthanide ions, and their enantiomorphs form racemate crystals. Luminescence studies have been carried out on the solid and solution-state samples. The triplet energy levels of Me(3)L, H(3)L, and H(2)L are 21?000, 22?700, and 23?000 cm(-1), respectively, which were determined from the phosphorescence spectra of their Gd(3+) complexes. The Me(3)L ligand is an effective sensitizer for Sm(3+) and Eu(3+) ions. Efficient luminescence of Sm(3+), Eu(3+), Tb(3+), and Dy(3+) ions was observed in complexes with the H(3)L and H(2)L ligands. Ligand modification by changing imidazole groups alters their triplet energy, and results in different sensitizing ability towards lanthanide ions.     

Synthesis and crystal structure of [Ln(4-Pyta)3(H2O)2] n (Ln = Nd,Ce, Eu,Gd; 4-Pyta = 4-pyridylthioacetate)

Four new lanthanide complexes, [Nd(4-Pyta)₃(H₂O)₂] _n (1), [Ce(4-Pyta)₃(H₂O)₂] _n (2), [Eu(4-Pyta)₃(H₂O)₂] _n (3) and [Gd(4-Pyta)₃(H₂O)₂] _n (4), have been obtained from reaction of lanthanide(III) nitrate with 4-Pyta (4-pyridylthioacetate) in water. Their structures were characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. The crystals belong to triclinic, space group P 1 and all complexes exhibit one-dimensional chains that arrange to form a three-dimensional supramolecular architecture by hydrogen bonds between the chains.     

CO activation on the late lanthanide dimers: matrix infrared spectra of the Ln2[eta2(mu2-C, O)]x (Ln = Tb, Dy, Ho, Er, Lu; x = 1, 2) molecules

Reactions of laser-ablated late lanthanide atoms (Tb, Dy, Ho, Er, Tm, Yb, and Lu) with dilute carbon monoxide molecules in solid argon have been investigated using matrix-isolation infrared spectroscopy. The Ln2[eta2(mu2-C, O)]x (Ln = Tb, Dy, Ho, Er, Lu; x = 1, 2) molecules are observed upon sample annealing, whereas no product is observed for Tm and Yb. The C-O stretching frequencies in these dilanthanide carbonyls range from 1100 to 1300 cm-1, far below the value of free CO in the gas phase (2143.5 cm-1), implying that the C-O bonds are highly activated. Density functional theory calculations have been performed on these products. These Ln2[eta2(mu2-C, O)]x molecules are predicted to have planar structures, which carry asymmetrically bridging CO moieties that are tilted to the side.     

Crystal Structures of Ln（NO3）3（Ln=La,Yb）Complexes with 12—crown—4

ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｓｏｆＬｎ（ＮＯ_３）_３（Ｌｎ＝Ｌａ，Ｙｂ）Ｃｏｍｐｌｅｘｅｓｗｉｔｈ１２－ｃｒｏｗｎ－４ＭａｏＪｉａｎｇ－Ｇａｏ；ＪｉｎＺｈｏｎｇ－Ｓｈｅｎｇ；ＹｕＦｅｎｇ－Ｌａｎ（ＬａｂｏｒａｔｏｒｙｏｆＲａｒｅＥａｒｔｈＣｈｅｍ...     

Diplatinum alkynyl chromophores as sensitisers for lanthanide luminescence in Pt2Ln2 and Pt2Ln4 (Ln = Eu, Nd, Yb) arrays with acetylide-functionalized bipyridine/phenanthroline

Incorporation of diplatinum complex Pt2(micro-dppm)2(bpyC[triple bond]C)4 or Pt2(mu-dppm)2(phenC[triple bond]C)4 with Ln(hfac)3(H2O)2 (Ln = Nd, Eu, Yb) gave a series of Pt2Ln2 and Pt2Ln4 bimetallic arrays, in which the excitation of d(Pt) -->pi*(R-C[triple bond]C) MLCT absorption induces sensitisation of lanthanide luminescence through efficient d --> f energy transfer from Pt(II) alkynyl chromophores.     

Phase diagrams of the SrEr2S4-SrLn2S4 (Ln = Nd, Dy, Yb) systems

The phase diagrams of the SrEr₂S₄-SrLn₂S₄ (Ln = Nd, Dy, Yb) systems were constructed, and the diagrams of the SrLn??₂S₄-SrLn??₂S₄ (Ln??, Ln?? = La-Lu) systems were predicted. The diagram of the SrEr₂S₄-SrNd₂S₄ system is of the eutectic type. The diagrams of the SrEr₂S₄-SrDy₂S₄ and SrEr₂S₄-SrYb₂S₄ systems involve the formation of a continuous series of solid solutions with the rhombic structure of the CaFe₂O₄.     

Conductivity of nonstoichiometric fluorides LnF2+x (Ln = Sm,Eu, Yb)

Nonstoichiometric fluorides LnF_2+x (Ln = Sm, Eu, Yb) were synthesized by reduction of trifluorides with the above rare-earth elements. The resulting phases were identified by chemical and X-ray phase analyses, their composition and structure were determined, and their lattice constants were found. The ac bridge method at a frequency of 70 kHz was used to study the conductivity of the synthesized compounds and starting trifluorides in the temperature range 773–298 K. The temperature dependence of the conductivity of these compounds is satisfactorily approximated by the Arrhenius-Frenkel equation. A kink is observed on the plots of the electrical conductivity against temperature for all compounds. With decreasing content of fluorine, this kink shifts to higher temperatures. The highest conductivity is observed for the phases with low crystal packing density. With increasing content of fluorine, the conductivity of all nonstoichiometric phases not belonging to substitution solid solutions approaches the conductivity of the corresponding trifluorides.     

RE[CH2（CH2）4CONC4H9]3（NO3）3（RE=La,Dy）的合成和晶体结构

采用Ｘ－射线四园衍射仪测定了Ｄｙ「Ｃｈ２（ＣＨ２）４ＣＯＮＣ４Ｈ９」３（ＮＯ３）３和Ｌａ「ＣＨ２（ＣＨ２）４ＣＯＮＣ４Ｈ３」３（ＮＯ３）３的晶体结构。两个配合物具有相似的结构，均属单斜晶系，空间群为Ｐ２１／ｃ。晶体参数：Ｄｙ「Ｌａ」：ａ＝１．８５６４（３）「１．８５６４（２）」ｎｍ，ｂ＝０．９７６９（２）「０．９８３４（１）」ｎｍ，ｃ＝２．１８６３（６）「２．２００３８（７）」ｎｍ，β＝９６．０８     

Solvothermal syntheses, and characterization of [Ln(en)4(SbSe4)] (Ln=Ce, Pr) and [Ln(en)4]SbSe4·0.5en (Ln=Eu, Gd, Er, Tm, Yb): The effect of lanthanide contraction on the crystal structures of lanthanide selenidoantimonates(V)

Two types of lanthanide selenidoantimonates [Ln(en)₄(SbSe₄)] (Ln=Ce(1a), Pr(1b)) and [Ln(en)₄]SbSe₄·0.5en (Ln=Eu(2a), Gd(2b), Er(2c), Tm(2d), Yb(2e); en=ethylenediamine) were solvothermally synthesized by reactions of LnCl₃, Sb and Se with the stoichiometric ratio in en solvent at 140 °C. The four-en coordinated lanthanide complex cation [Ln(en)₄]³⁺ formed in situ balances the charge of SbSe₄³⁻ anion. In compounds 1a and 1b, the SbSe₄³⁻ anion act as a monodentate ligand to coordinate complex [Ln(en)₄]³⁺ and the neutral compound [Ln(en)₄(SbSe₄)] is formed. The Ln³⁺ ion has a nine-coordinated environment involving eight N atoms and one Se atom forming a distorted monocapped square antiprism. In 2a-2e the lanthanide(III) ion exists as isolated complex [Ln(en)₄]³⁺, in which the Ln³⁺ ion is in a bicapped trigonal prism geometry. A systematic investigation of the crystal structures reveals that two types of structural features of these lanthanide selenidoantimonates are related with lanthanides contraction across the lanthanide series. TG curves show that compounds 1a-1b and 2a-2e remove their organic components in one and two steps, respectively.     

Near-infrared luminescent hybrid materials doped with lanthanide (Ln) complexes (Ln = Nd, Yb) and their possible laser application

The crystal structures of ternary Ln(DBM)(3)phen complexes (DBM = dibenzoylmethane, phen = 1,10-phenanthroline, and Ln = Nd, Yb) and their in situ syntheses via the sol-gel process are reported. The properties of the Ln(DBM)(3)phen complexes and their corresponding Ln(3+)/DBM/phen-co-doped luminescent hybrid gels obtained via an in situ method (Ln-D-P gel) have been studied. The results reveal that the lanthanide complexes are successfully in situ synthesized in the corresponding Ln-D-P gels. Both Ln(DBM)(3)phen complexes and Ln-D-P gels display sensitized near-infrared (NIR) luminescence upon excitation at the maximum absorption of the ligands, which contributes to the efficient energy transfer from the ligands to the Ln(3+) ions (Ln = Nd, Yb), an antenna effect. The radiative properties of the Nd(3+) ion in a Nd-D-P gel are discussed using Judd-Ofelt analysis, which indicates that the (4)F(3/2) --> (4)I(11/2) transition of the Nd(3+) ion in the Nd-D-P gel can be considered as a possible laser transition.     

Cluster-type basic lanthanide iodides [M6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 (M = Nd, Eu, Tb, Dy)

Ln6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)(8) (Ln = Nd, Eu, Tb, Dy) compounds are obtained as the final hydrolysis products of lanthanide triiodides in an aqueous solution. Their X-ray crystal structure features a body-centered arrangement of oxygen-centered {Ln6X8}8+ cluster cores: [Nd6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1310.4(3) pm, b = 1502.1(3) pm, c = 1514.9(3) pm, 3384 reflections with I0 > 2sigma(I0), R1 = 0.0340, wR2 = 0.0764, GOF = 1.022, T = 298(2) K], [Eu6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1306.6(2) pm, b = 1498.15(19) pm, c = 1499.41(18) pm, 4262 reflections with I0 > 2sigma(I0), R1 = 0.0540, wR2 = 0.0860, GOF = 0.910, T = 298(2) K], [Tb6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1296.34(5) pm, b = 1486.13(7) pm, c = 1491.88(6) pm, 4182 reflections with I0 > 2sigma(I0), R1 = 0.0395, wR2 = 0.0924, GOF = 1.000, T = 298(2) K], and [Dy6(mu6-O)(mu3-OH)8(H2O)24]I8(H2O)8 [Pearson code oP156, orthorhombic, Pnnm (No. 58), Z = 2, a = 1296.34(5) pm, b = 1486.13(7) pm, c = 1491.88(6) pm, 3329 reflections with I0 > 2sigma(I0), R1 = 0.0389, wR2 = 0.0801, GOF = 0.992, T = 298(2) K.     

Structures of nonlinear hexagonal boratotungstates Ln3BWO9 (Ln = La, Pr, Nd, Sm, Gd, Tb, Dy)

Polycrystalline boratotungstates of composition Ln₃BWO₉ (Ln = Pr, Nd, Sm, Gd, Tb, Dy) are prepared by solid-phase synthesis and structurally studied. The structures are refined using the Rietveld method for hexagonal space group P6₃ (Z = 2). The boratotungstate structures are frameworks. The rare-earth cations in the structure are coordinated by an array of nine oxygen atoms (three oxygen atoms from borato groups BO₃ and six from WO₆ polyhedra). The nature of the optical nonlinearity in the hexagonal boratotungstates Ln₃BWO₉ is a direct consequence of the acentricity of both the tungstate and the rare-earth polyhedra in the structure. Dimorphism is discovered in polycrystalline La₃BWO₉.     

Crystal structures of Ln4Ni3O8 (Ln = La, Nd) triple layer T'-type nickelates

Single-phase Ln4Ni3O8 (Ln = La, Nd) nickelates were synthesized and their crystal structures were determined by Rietveld refinement of powder neutron diffraction data. The crystal structures of these mixed-valent Ni1+/Ni2+ phases belong to the T'-type and are built by intergrowth of LnO2 fluorite layers with triple NiO2 infinite-layer structural blocks. The major driving force of transformation of the LnO rock-salt block of the parent Ln4Ni3O10-delta Ruddlesden-Popper phases to the fluorite arrangement in the reduced Ln4Ni3O8 phases is attributed to internal structural stress. This transformation allows longer Ni-O bonds in Ln4Ni3O8 without overstretching of the Ln-O bonds, especially in the equatorial plane. The observed displacement of Ni atoms from the outer NiO2 planes toward the Ni atom of the central NiO2 plane in Ln4Ni3O8 is ascribed to large electrostatic repulsion from the fluorite part of the structure. X-ray absorption spectra near the K-edge of Ni suggest that the charge density on the nickel ion is similar for all members of the T'-type Lnn+1NinO2n+2 homologous series, which correlates with nearly constant Ni-O bond lengths observed in all the reduced nickelates. This suggests that the formal changes in the valence state of Ni affect the covalency of the Ni-O bond.     

稀土配合物Et~2NC~6H~4CH=CHC~5H~4NC~1~6H~3~3Ln(TTA)~4(Ln=La,Nd,Dy,Yb)的合成、表征与成膜性能

合成了四(α-噻吩甲酰三氟丙酮)合稀土(La,Nd,Dy,Yb)酸(E)-N-十六烷基-4-[2-(4-二乙氨基苯基)乙烯基]吡啶四个新的稀土配合物。用元素分析、紫外可见光谱、红外光谱、小角X射线衍射、差热-热重分析和摩尔电导对配合物进行了表征。研究了它们的表面压-面积(π-A)等温线行为。研究结果表明它们具有良好的成膜(Langmuir)性能, La, Nd, Dy和Yb配合物零压分子平均截面积A~π~→~0分别为1.94,1.93,1,73和1.85nm^2/分子。     

Direct solvothermal growth, crystal structures, and optical properties of one-dimensional lanthanide selenidoarsenate(v) polymers [Ln(dien)2(micro3-AsSe4)] (Ln = Nd, Sm): the first example of an AsSe4(3-) anion acting as a ligand to a lanthanide complex

Two novel lanthanide selenidoarsenates(v) [Ln(dien)2(micro(3)-AsSe(4))] (Ln = Nd 1, Sm 2, dien = diethylenetriamine) were synthesized by the reactions of As(2)O(3) and Se with Nd(2)O(3) or Sm(2)O(3) in dien under solvothermal conditions. 1 and 2 are in the orthorhombic crystal system with Iba2 and Pbca space groups, respectively. The [AsSe(4)](3-) anion acts as a tridentate micro(3)-AsSe(4) ligand to bridge the lanthanide [Ln(dien)2](3+) complexes leading to one-dimensional neutral [Ln(dien)(2)(micro(3)-AsSe(4))](infinity) chains. The chains contact through hydrogen bonding to form network structures. The lanthanide center lies within a nine-coordinated environment involving six N atoms of two dien ligands and three Se atoms of two different tetrahedral [AsSe(4)](3-) anions forming a distorted monocapped square antiprism. The novel coordination polymers [Nd(dien)2(micro(3)-AsSe(4))](infinity) and [Sm(dien)2(micro(3)-AsSe(4))](infinity) are the first examples of solvothermally synthesized selenidoarsenates with [AsSe(4)](3-) anion acting as a ligand in lanthanide complexes. The band gaps of 2.11 eV for 1, and 2.18 eV for 2 have been derived from optical absorption spectra. TG-DSC curves show that two compounds remove coordinated dien ligands in a single step.     

On the Perovskites Ba2LnSbO6 (Ln = Nd,Sm, Eu,Gd, Tb,Dy, Ho,Er, Yb)

Polycrystalline Ba₂LnSbO₆ (Ln = Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb) are cubic, perovskite-type compounds, space group Fm3m (No. 225), Z = 4, with a values from a = 8.544(2) Å for Ba₂NdSbO₆ to a = 8.368(1) Å for Ba₂YbSbO₆. X-ray diffraction data for all the compounds and the results of magnetic measurements for two of them are given.