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1.
The usage of the achiral ligand, in lanthanide chemistry, successfully obtained two series of chiral lanthanide complexes, formulated d - and l -{Gd[IN][HIN][CH2OCH2O]}n (abbreviated as Gd ) and d - and l -{Dy[IN][HIN][CH2OCH2O]}n (abbreviated as Dy , HIN = isonicotinic acid). Crystallographic researches determined that four compounds are all one-dimensional (1D) chain structures and crystallized in a chiral space group. In addition, CH2OHCH2OH acts as not only solvent but also the bridge ligand. Besides, single crystal circular dichroism (CD) spectra conformed compounds Gd-L and Gd-D , Dy-L and Dy-D are enantiomers respectively. Magnetically, compound Gd showed predominant magnetocaloric effect (MCE) of 26.20 J · kg–1 · K–1 at 2.5 K for ΔH = 7 T, while there is ferromagnetic interactions in compound Dy .  相似文献   

2.
The compound [VO(dien)]2GeS4 ( 1 , dien = diethylenetriamine) features an ortho‐thiogermanate anion [GeS4]4–, which acts as tetradentate ligand joining [VO(dien)]2– complexes. The compound was obtained under solvothermal conditions crystallizing in thenon‐centrosymmetric orthorhombic space group Pna21 with a =19.8310(11), b = 8.0814(5), c = 12.0889(9) Å, V = 1937.4(2) Å3 and Z = 4. The V4+ cations are in a distorted octahedral environment of a tridentate dien molecule, one oxygen atom and two sulfur atoms from the [GeS4]4– anion. A three‐dimensional network is generated by hydrogen bonding interactions.  相似文献   

3.
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.  相似文献   

4.
The four new compounds CsTmCoS3, CsYbCoS3, CsHoCoSe3, and CsYbCoSe3 have been synthesized at 1123 K. These black‐colored isostructural compounds crystallize in the KZrCuS3 structure type with four formula units in space group Cmcm of the orthorhombic system. The structure of these compounds is composed of layers separated by Cs atoms. Because there are no Q–Q bonds, the formal oxidation states of Cs/Ln/Co/Q are 1+/3+/2+/2?, respectively. CsHoCoSe3 shows paramagnetic behavior with μeff = 11.9(1) μB, whereas CsYbCoS3 displays an antiferromagnetic‐like transition at ~2.7 K with μeff = 5.85(1) μB. Both CsYbCoS3 and CsYbCoSe3 exhibit optical band gaps in the near infrared region and broad absorption bands at lower energies.  相似文献   

5.
Syntheses and Crystal Structures of New Alkali Metal Rare‐Earth Tellurides of the Compositions KLnTe2 (Ln = La, Pr, Nd, Gd), RbLnTe2 (Ln = Ce, Nd) and CsLnTe2 (Ln = Nd) Of the compounds ALnQ2 (A = Na, K, Rb, Cs; Ln = rare earth‐metal; Q = S, Se, Te) the crystal structures of the new tellurides KLaTe2, KPrTe2, KNdTe2, KGdTe2, RbCeTe2, RbNdTe2, and CsNdTe2 were determined by single‐crystal X‐ray analyses. They all crystallize in the α‐NaFeO2 type with space group R3¯m and three formula units in the unit cell. The lattice parameters are: KLaTe2: a = 466.63(3) pm, c = 2441.1(3) pm; KPrTe2: a = 459.73(2) pm, c = 2439.8(1) pm; KNdTe2: a = 457.83(3) pm, c = 2443.9(2) pm; KGdTe2: a = 449.71(2) pm, c = 2443.3(1) pm; RbCeTe2: a = 465.18(2) pm, c = 2533.6(2) pm; RbNdTe2: a = 459.80(3) pm, c = 2536.5(2) pm, and CsNdTe2: a = 461.42(3) pm, c = 2553.9(3) pm. Characteristics of the α‐NaFeO2 structure type as an ordered substitutional variant of the rock‐salt (NaCl) type are layers of corner‐sharing [(A+/Ln3+)(Te2—)6] octahedra with a layerwise alternating occupation by the cations A+ and Ln3+.  相似文献   

6.
The compounds TlLn(SO4)2·2H2OLn=La, Ce, Pr, Nd and Tl[Ln(SO4)2(H2O)3]·H2OLn=Nd, Sm, Eu, Gd, Tb have been isolated from aqueous solutions of the corresponding sulfates. The dihydrates are all isomorphous and crystallize monoclinic, space groupP21/n,Z=4. The compounds which belong to the second type are also isomorphous and crystallize in monoclinic space groupP 21/c withZ=4.The dehydration has been studied by thermogravimetry, differential scanning calorimetry and isothermal weight change determination. The dihydrates dehydrate in a single step. For the tetrahydrates the reaction is more complex, however no intermediate phases could be isolated.The unit cell parameters, the dehydration temperatures and the dehydration enthalpies are correlated to the ionic radii ofLn 3+.
Synthese und Charakterisierung von TlLn(SO4)2·xH2O (Ln=La-Tb)
Zusammenfassung Die Verbindungen TlLn(SO4)2·2H2OLn=La, Ce, Pr, Nd und Tl[Ln(SO4)2(H2O)3]·H2OLn=Nd, Sm, Eu, Gd, Tb wurden aus wäßrigen Lösungen der entsprechenden Sulfate isoliert. Die Dihydrate sind alle isomorph und kristallisieren monoklin, RaumgruppeP 21/n,Z=4. Die Verbindungen des zweiten Typs sind auch isomorph und kristallisieren in der monoklinen RaumgruppeP 21/c mitZ=4.Die Dehydration wurde mit TG, DSC und dem isothermalen Gewichtsverlust untersucht. Die Entwässerung der Dihydrate verläuft in einer Stufe, die von Tetrahydraten aber in mehreren Stufen mit keiner isolierbaren Zwischenphase.Die Gitterkonstanten, die Dehydratations-Temperaturen und -Enthalpien wurden mit den Ionenradien vonLn 3+ korreliert.
  相似文献   

7.
单分子磁体[Mn4(CF3COO)4(hmp)6]的合成、晶体结构及磁学性质   总被引:1,自引:0,他引:1  
以[Mn12O12(CF3COO)16(H2O)4]·2CF3COOH·4H2O和2-羟甲基吡啶(hmpH)为起始物, 在四氢呋喃溶液中合成了一种新的四核锰配合物[Mn4(CF3COO)4(hmp)6]. X射线单晶衍射结果表明, 该配合物属于单斜晶系, P21/c空间群, 晶胞参数a=1.3663(3) nm, b=1.4705(3) nm, c=1.4734(3) nm, β=98.51(3) °, V=2.9276 nm3, Z=2. 配合物中有两个CF3COO-基团与七配位Mn2中心相连, 其中一个为单齿配体, 另一个是双齿配体. 直流磁化率研究结果表明, 该配合物具有较高的自旋基态, 而交流磁化率依赖于外场频率变化极值的出现表明该配合物是一种单分子磁体.  相似文献   

8.
Abstract. Two radical–LnIII–radical complexes, [Ln(hfac)3(NITPh‐Ph)2] [Ln = Gd ( 1 ) and Ho ( 2 ), hfac = hexafluoroacetylacetonate; and NITPh‐Ph = 4′‐biphenyl‐4, 4, 5, 5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide] were synthesized and characterized by X‐ray diffraction, elemental analysis, magnetic measurements, as well as IR and UV/Vis spectroscopy. X‐ray crystal structure analysis revealed that the structures of both complexes are isomorphous, the central LnIII ions are coordinated by six oxygen atoms from three hfac ligand molecules and two oxygen atoms from nitronyl radicals. The temperature dependencies of the magnetic susceptibilities were studied. They showed that in the GdIII complex, ferromagnetic interactions between GdIII and the radicals and antiferromagnetic interactions between the radicals coexist in this system (with JRad–Gd = 0.1 cm–1, JRad–Rad = –0.309 cm–1).  相似文献   

9.
Two tetranuclear clusters of formula [M4L4(HOMe)4] {H2L = (E)‐1‐[(2‐(hydroxymethyl)phenylimino)methyl]naphthalen‐2‐ol} [M = Co ( 1 ), Ni ( 2 )] were hydrothermally synthesized by reaction of M(OAc)2 · 4H2O with H2L and NaOH in MeOH. X‐ray crystal structure analysis revealed that complexes 1 and 2 are isostructural. In the core of the structures, four MII ions and four oxygen atoms occupied alternate vertices of [M4O4] cubane. The magnetic property measurements of 1 and 2 revealed that overall ferromagnetic MII ··· MII exchange interactions exist in both complexes.  相似文献   

10.
Three octacyanometallate‐based hetero‐bimetallic complexes, [Ln(H2O)4(CH3CN)2][M(CN)8] · CH3CN [Ln = La, M = Mo( 1 ), W( 2 ); Ln = Ce, M = W( 3 )], were synthesized and characterized structurally. Single‐crystal X‐ray analysis reveals that 1 – 3 are isomorphous and consist of infinite one‐dimensional (1D) 3,3 rope‐ladder chains, in which the 12‐membered puckered square Ln2M2(CN)4 is the basic building unit. The 1D chains are further linked through interchain hydrogen bonds, resulting in a three‐dimensional (3D) supramolecular network.  相似文献   

11.

Three ion-pair Ln-Cr complexes [Sm(DMA)4(H2O)3][Cr(CN)6] · 2H2O, [Gd(DMA)3(H2O)4][Cr(CN)6] · 2H2O and [Er(DMA)3(H2O)4][Cr(CN)6] (DMA = dimethylacetamide) have been synthesized. X-ray structure analyses of the title complexes revealed that there is a hydrogen-bonding network through CN groups and H2O molecules. Variable temperature magnetic susceptibilities indicate weak antiferromagnetic interactions between cation and anion pairs moderated through the hydrogen bonding network.  相似文献   

12.
The lanthanide chloride ortho‐oxomolybdates LnCl[MoO4] (Ln = La, Ce, Pr) crystallize in the monoclinic space group P21/c(a = 1921–1906 pm, b ≈? 580 pm, c = 804–789 pm, β ≈? 90.04°, Z = 8).In the crystal structure, two crystallographically unique Ln3+ cations are present, both with the same coordination environment of four Cl and six O2– anions in the shape of a distorted tetracapped trigonal prism. The two distinguishable Cl anions both display a coordination sphere of three plus one Ln3+ cations, building up distorted tetrahedra. These are fused together via four common edges to form litharge‐analogous layers (e = edge‐connecting) parallel to the (100) plane. Two crystallographically different oxomolybdate units are also found in the structure, which can be best described as strandsof apically vertex‐shared [MoO5]4– trigonal bipyramids of the formula (v = vertex‐connecting, t = terminal) along [001]. These building blocks, the layers and the chains are alternately stacked along the a axis. The peculiarity of this structure is expressed by the position of the Mo6+ cations, which are not situated in the center of the bipyramids, but reside offset in their lower or upper trigonal pyramids (≈? tetrahedra). The Mo6+ cations with an x / a parameter between 0 and 0.5 can be found within the lower trigonal pyramids of those bipyramids (if viewed along the [001] direction), whereas those with 0.5 < x / a < 1 are located in the upper trigonal pyramid. Therefore, an alternating arrangement of the strands is observed. Due to the special constitution of the Ln3+ cations in distorted litharge‐analogous layers, a special magnetic effect was assumed, but in phase‐pure samples of e.g. CeCl[MoO4] mainly Curie–Weiss behavior could be detected.  相似文献   

13.
Three dinuclear lanthanide complexes [Ln2(H2L)2(NO3)4] [Ln = Dy ( 1 ), Tb ( 2 ), and Gd ( 3 )] [H3L = 2‐hydroxyimino‐N′‐[(2‐hydroxy‐3‐methoxyphenyl)methylidene]‐propanohydrazone] were solvothermally synthesized by varying differently anisotropic rare earth ions. Single‐crystal structural analyses demonstrate that all the three complexes are crystallographically isostructural with two centrosymmetric LnIII ions aggregated by a pair of monodeprotonated H2L anions. Weak intramolecular antiferromagnetic interactions with different strength were mediated by a pair of phenoxo bridges due to superexchange and/or single‐ion anisotropy. Additionally, the DyIII‐based entity shows the strongest anisotropy exhibits field‐induced single‐molecule magnetic behavior with two thermally activated relaxation processes. In contrast, 3 with isotropic GdIII ion has a significant cryogenic magnetocaloric effect with the maximum entropy change of 25.7 J · kg–1 · K–1 at 2.0 K and 70.0 kOe.  相似文献   

14.
在本研究中,使用(iPrC6H4SAg)n作为合成银硫纳米簇合物的前驱体。当存在辅助的双膦配体1, 3-双(二苯基膦)丙烷(dppp)及可溶性银盐(CF3SO3Ag),在超声合成条件下,获得了一例二十五核银硫簇合物Ag25,并借助X射线单晶衍射技术确定相应的分子结构。该银硫簇合物具有夹心三明治的骨架结构:分别由两个结构相似的圆柱体共享一个七核纯银簇所构成的金属簇平面。固态紫外可见漫反射光谱测试表明该簇合物的能级带隙为2.5 eV,属于半导体材料的范畴。固态发光测试显示,该簇合物在室温下发射绿光。  相似文献   

15.
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   

16.
Two N'-(2-hydroxybenzylidene)pyridine N-oxide-carbohydrazide (H3L)-based coordination complexes with the formula [Ln2(DMF)2(OAc)2(HL)2]n (Ln = Dy for 1 and Eu for 2 ) were solvothermally synthesized. Crystal structures, thermal stabilities, magnetic and luminescent properties of the two complexes were fully investigated. Both complexes are isomorphic two-dimensional layers with centrosymmetric {Ln2} subunits extended by doubly deprotonated HL2– connectors. Complex 1 with highly anisotropic DyIII spin exhibits slightly frequency-dependent magnetic relaxations under zero dc field with an effective energy barrier of ca. 6.84 K. EuIII-based complex 2 displays only one weak fluorescent emission around 532 nm with the absence of characteristic emission of EuIII ion. These results provide helpful hints of the hydrazide Schiff-functionalized organic ligands on the function modulations of the resulting Ln complexes.  相似文献   

17.
Nd(S2O7)(HSO4): The First Disulfate of a Rare Earth Element Light violett single crystals of Nd(S2O7)(HSO4) have been obtained by the reaction of Nd2O3 and oleum (30% SO3) at 200 °C in sealed glass ampoules. The crystal structure (monoclinic, P21/n, Z = 4, a = 857.8(1), b = 1061.0(2), c = 972.4(1) pm, β = 99.33(2)°) contains Nd3+ in eightfold coordination of oxygen atoms which belong to three HSO4 ions and four S2O72– groups. One of the latter acts as bidentate ligand. Hydrogen bonding is observed between the H atom of the HSO4 ion and the non‐coordinating O atom of the S2O72– group.  相似文献   

18.
The ternary indium compounds RE4Pd10In21 (RE = La, Ce, Pr, Nd, Sm) were synthesized from the elements in glassy carbon crucibles in a high‐frequency furnace. Single crystals of Sm4Pd10In21 were obtained from an indium flux. An arc‐melted precursor alloy of the starting composition ~SmPd3In6 was annealed with a slight excess of indium at 1200 K followed by slow cooling (5 K/h) to 870 K. All compounds were investigated by X‐ray powder diffraction and the structures were refined from single crystal diffractometer data. The RE4Pd10In21 indides are isotypic with Ho4Ni10Ga21, space group C2/m: a = 2314.3(2), b = 454.70(7), c = 1940.7(2) pm, β = 133.43(2)°, wR2 = 0.0681, 1678 F2 values for La4Pd10In21, a = 2308.2(1), b = 452.52(4), c = 1944.80(9) pm, β = 133.40(1)°, wR2 = 0.0659, 1684 F2 values for Ce4Pd10In21, a = 2303.8(2), b = 450.78(4), c = 1940.6(1) pm, β = 133.39(1)°, wR2 = 0.0513, 1648 F2 values for Pr4Pd10In21, a = 2300.2(2), b = 449.75(6), c = 1937.8(2) pm, β = 133.32(1)°, wR2 = 0.1086, 1506 F2 values for Nd4Pd10In21, and a = 2295.6(2), b = 447.07(4), c = 1935.7(1) pm, β = 133.16(1)°, wR2 = 0.2291, 2350 F2 values for Sm4Pd10In21, with 108 variables per refinement. All palladium atoms have a trigonal prismatic coordination. The strongest bonding interactions occur for the Pd—In and In—In contacts. The structures are composed of covalently bonded three‐dimensional [Pd10In21] networks in which the rare earth metal atoms fill distorted pentagonal channels. The crystal chemistry and chemical bonding in these indides is briefly discussed. Magnetic susceptibility measurements show diamagnetism for La4Pd10In21 and Curie‐Weiss paramagnetism for Ce4Pd10In21, Pr4Pd10In21, and Nd4Pd10In21. The neodymium compound orders antiferromagnetically at TN = 4.5(2) K and undergoes a metamagnetic transition at a critical field of 1.5(2) T. All the RE4Pd10In21 indides studied are metallic conductors.  相似文献   

19.
A novel complex [Li3{μ‐(H2O)6}(H2O)6]·[RuCl6] has been synthesized and was characterized by single‐crystal X‐ray diffraction. The compound crystallizes in rhombohedral space group Rc, with the unit cell parameters a = b = 9.948(2)Å, c = 33.376(14)Å, γ = 120°, V = 2860.5(15)Å3, Z = 6, Dc = 1.918 Mg m—3, μ = 1.703 mm—1, R = 0.0244, wR = 0.0478. The compound consists of a cation, which contains three lithium ions linked by six bridged water molecules, and an anion, which contains a ruthenium(III) ion. The whole complex can be described as a three‐dimensional structure linked by hydrogen bonds between cation and anion. The magnetic properties of the complex have been investigated. The IR, UV‐vis and EPR spectra are studied.  相似文献   

20.
Preparation and Crystal Structures of New Complex Clorides of Lanthanides containing 3, 5‐Dimethylpyridinium Cations: (3, 5‐Dimethylpyridinium)2[LnCl4(H2O)2]Cl (Ln = La, Pr) and (3, 5‐Dimethylpyridinium)3[TbCl6] Crystals of the complex chlorides (3, 5‐dimethylpyridinium)2[LaCl4(H2O)2]Cl ( 1 ), (3, 5‐dimethylpyridinium)2[PrCl4(H2O)2]Cl ( 2 ) and (3, 5‐dimethylpyridinium)3[TbCl6] ( 3 ) have been prepared by reaction of LnCl3 · x H2O (Ln = La, Pr, Tb; x = 6‐7) with 3, 5‐dimethylpyridiniumchloride in ethanol/butanol solution. The crystal structures have been determined from single crystal X‐ray diffraction data. The compounds 1 and 2 are isotypic with each other and crystallize in the triclinic space group P1¯ (Z = 2). The 3, 5‐dimethylpyridinium cations are linked by hydrogen bonds to the anionic part of the structure built up by isolated chloride ions and strings of edge coupled triangulated dodecahedra [LnCl4/2Cl2(H2O)2]. The organic units are arranged forming a “π‐stacking”. 3 cristallizes monoclinically in the space group P21/c (Z = 4). The structure contains octahedral building units [TbCl6]3—. These octahedra are interconnected by the organic cations via hydrogen bonds forming chains parallel to [0 0 1].  相似文献   

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