Darstellung,Kristallstrukturen und Eigenschaften von Ln4Au2O9 (Ln = Nd,Sm, Eu)

Syntheses, Crystal Structures, and Properties of Ln₄Au₂O₉ (Ln = Nd, Sm, Eu) The compounds Ln₄Au₂O₉ (Ln = Nd, Sm, Eu) have been prepared from amorphous Au₂O₃ · 2–3 H₂O and Ln₂O₃ (Ln = Nd, Sm, Eu) via solid state reaction under elevated oxygen pressure adding KOH as mineralising agent. They are isostructural with La₄Au₂O₉ (Nd₄Au₂O₉: a = 11.9813(3), b = 6.1474(1), c = 11.9641(4); 453 powder intensities, R_p = 3.75%; Sm₄Au₂O₉: a = 11.8689(4), b = 6.0360(1), c = 11.8469(4) Å; 812 unique reflections, R₁ = 2.75%; Eu₄Au₂O₉: a = 11.8241(3), b = 5.9922(1) Å, c = 11.8013(3) Å; 1315 unique reflections, R₁ = 7.83%). The crystal structure of Nd₄Au₂O₉ was refined from powder diffraction data. The structures of Sm₄Au₂O₉ and Eu₄Au₂O₉ were solved and refined from single crystal data. The isolated square planar AuO₄ units are stacked as columns and are linked to each other by LnO₇‐polyhedra. One of the oxygen atoms is exclusively connected to the trivalent lanthanides in tetrahedral geometry. Ln₄Au₂O₉, Bi₂CuO₄, Bi₂AuO₅ and Bi₄Au₂O₉ are closely related, structurally. The lanthanoid aurates decompose between 700 and 800 °C into Ln₂O₃, Au and O₂. The effective magnetic moments 3.64 μ_B (Nd₄Au₂O₉), 1.7 μ_B (Sm₄Au₂O₉) and 3.3 μ_B (Eu₄Au₂O₉) confirm that the lanthanides are trivalent. The UV/VIS absorption spectra can be interpreted at assuming free ions.     

Synthese und Kristallstruktur von Ln2SeSiO4 (Ln = Sm,Dy, Ho) und Sm2TeSiO4

Synthesis and Crystal Structure of Ln₂SeSiO₄ (Ln = Sm, Dy, Ho) and Sm₂TeSiO₄ Single crystals of Ln₂SeSiO₄ (Ln = Sm, Dy, Ho) could be prepared by the reaction of lanthanide metal, selenium and iodine in the ratio 1 : 1 : 2.5 and subsequent reaction with quartz glass powder. Black crystals of Sm₂TeSiO₄ have been obtained in chemical transport experiments of SmTe₂ with iodine in evacuated quartz glass ampoules as by‐products. All chalcogenide silicates crystallize orthorhombically with the space group Pbcm (Z = 4) and the lattice constants: Sm₂SeSiO₄: a = 612.6(1) pm, b = 709.0(1) pm, c = 1094.0(2) pm; Dy₂SeSiO₄: a = 603.6(1) pm, b = 696.4(1) pm, c = 1081.2(2) pm; Ho₂SeSiO₄: a = 601.0(1) pm, b = 693.6(1) pm, c = 1078.6(2) pm; Sm₂TeSiO₄: a = 623.82(8) pm, b = 713.06(7) pm, c = 1112.26(11) pm. The crystal structure is built up of alternating Ln(Se/Te) and LnSiO₄ sheets parallel (001).     

Syntheses and Crystal Structures of Ln(phen)2(NO3)3 with Ln = Pr,Nd, Sm,Eu, Dy,and phen = 1,10‐phenanthroline

Five new complex compounds of the formula Ln(phen)₂(NO₃)₃ were prepared. The X‐ray structural analyses indicate that they crystallize isostructurally in the monoclinic space group C2/c (no. 15) with cell dimensions for example for Pr(phen)₂(NO₃)₃: a = 11.194(1) Å, b = 18.095(2) Å, c = 13.101(2) Å, β = 100.52(1)°, V = 2609.1(6) ų, Z = 4. The crystal structures consist of [Ln(phen)₂(NO₃)₃] complex molecules. The rare earth atoms are coordinated by four N atoms of two phen ligands and six O atoms of three nitrato groups to complete a distorted bicapped dodecahedron. The [Ln(phen)₂(NO₃)₃] complex molecules are assembled via π‐π stacking interactions between the neighboring phen ligands to form 1D columnar chains, which are then arranged in the crystal structures according to pseudo 1D close‐packed patterns.     

Synthese und Kristallstrukturen von Ln3I(SiS4)2 (Ln = Pr,Nd, Sm,Tb)

Synthesis and Crystal Structures of Ln₃I(SiS₄)₂ (Ln = Pr, Nd, Sm, Tb) Single crystals of Ln₃I(SiS₄)₂ were prepared by a two‐step reaction of lanthanide metal, sulfur, silicon and iodine in the ratio 1 : 3.25 : 1 : 0.33 in quartz glass tubes. The thiosilicates crystallize in the monoclinic space group C 2/c (Z = 4) isotypic to Ce₃I(SiS₄)₂ [1]. In the crystal structures the iodide ions form chains along [001] with trigonal coordination by lanthanide ions.     

Neue thermische Abbauprodukte von Ln2CeMO6Cl3 (M = Nb,Ta; Ln = La–Sm) – Darstellung von strukturverwandtem (La, Tb)3,5TaO6Cl4–x

Contributions on the Investigation of Inorganic Nonstoichiometric Compounds. XLV. New Thermal Decomposition Products of Ln₂CeMO₆Cl₃ – Preparation of Structure‐related (La, Tb)_3.5TaO₆Cl_4–x The thermal decomposition (T £ 900–1050°C) of Ln₂CeMO₆Cl₃ (M = Nb, Ta; Ln = La, Ce, Pr, Nd, Sm) leads to the formation of two mixed‐valenced phases (Ln, Ce)_3.25MO₆Cl_3.5–x (phase ‘‘AB”︁”︁) and (Ln, Ce)_3.5MO₆Cl_4–x (phase ‘‘BB”︁”︁) and to the formation of chlorine according to redox‐reactions between Ce⁴⁺ and Cl^–. Single crystals of both phases (Ln, Ce)_3.25MO₆Cl_3.5–x (‘‘AB”︁”︁) and (Ln, Ce)_3.5MO₆Cl_4–x (‘‘BB”︁”︁) were obtained by chemical transport reactions using both powder of Ln₂CeMO₆Cl₃ (phase ‘‘A”︁”︁) and powder of (Ln, Ce)_3.25MO₆Cl_3.5–x (phase ‘‘AB”︁”︁) as starting materials and chlorine (p{Cl₂; 298 K} = 1 atm) or HCl (p{HCl; 298 K} = 1 atm) as transport agent. A crystal of (La, Ce)_3.25NbO₆Cl_3.5–x (”︁AB”︁”︁) (space group: C2/m, a = 35.288(1) Å, b = 5.418(5) Å, c = 9.522(1) Å, β = 98.95(7)°, Z = 4) was investigated by x‐ray diffraction methods, a crystal of (Pr, Ce)_3.5NbO₆Cl_4–x (”︁BB”︁”︁) was investigated by synchrotron radiation (λ = 0.56 Å) diffraction methods. The lattice constants are a = 18.863(6) Å, b = 5.454(5) Å, c = 9.527(6) Å, β = 102.44(3)° and Z = 4. Structure determination in the space group C2/m (No. 12) let to R1 = 0.0313. Main building units are NbO₆‐polyhedra with slightly distorted trigonally prismatic environment for Nb and chains of face‐sharing Cl₆‐octahedra along [010]. The rare earth ions are coordinated by chlorine and oxygen atoms. These main structure features confirmed the expected relation to the starting material Ln₂CeMO₆Cl₃ (phase ”︁A”︁”︁) and to (Ln, Ce)_3.25MO₆Cl_3.5–x (phase ”︁AB”︁”︁).     

Darstellung,Struktur und magnetische Eigenschaften von Erdalkali-Mangan-Verbindungen AMnX mit A = Mg,Ca, Sr,Ba und X = Si,Ge, Sn

Preparation, Structure, and Magnetic Properties of the Alkaline Earth Manganese Compounds AMnX with A = Mg, Ca, Sr, Ba and X = Si, Ge, Sn The new compounds MgMnGe, MgMnSn, CaMnSi, CaMnSn, and SrMnSn were prepared by reaction of the elements. They crystallize tetragonally with the anti-PbFCl type structure (space group P4/nmm). The lattice constants see ”︁Inhaltsübersicht”︁”︁. Using a Faraday balance, magnetic measurements in the range 4.2 to 800 K were performed with the new substances and with the already known compounds CaMnGe, SrMnGe, and BaMnGe. They indicate metamagnetic behaviour at low temperatures. At high temperatures twodimensional magnetic interactions between the manganese atoms seem to persist. The construction of an unexpensive heating device for the Faraday balance is described.     

Chirality and Magnetic Properties of One-dimensional Ln (Ln = Gd,Dy) Polymers

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 .     

Darstellung,Kristallstruktur und magnetische Eigenschaften von In2Ni21B6

Preparation, Crystal Structure, and Magnetic Properties of In₂Ni₂₁B₆ In₂Ni₂₁B₆ was prepared by solid state reaction of the elements at 1223 K. The single‐crystals, obtained for the first time, exhibit metallic luster and crystallize in space group Fm 3 m (a = 1059.11(2) pm; Z = 4; 128 symmetry independent reflections; R1 = 0.027; wR2 = 0.125). In₂Ni₂₁B₆ is related to the Cr₂₃C₆‐structure and belongs to the structural family of τ‐borides. The compound melts at 1426 K. Polycrystalline samples of In₂Ni₂₁B₆ are ferromagnetic with a Curie‐Temperature of T_C = 596 K and show metallic conductivity in the range from 12 K to 320 K.     

Darstellung,Kristallstruktur und Eigenschaften von Kaliumhydrogencyanamid

Preparation, Crystal Structure, and Properties of Potassium Hydrogen Cyanamide For the preparation of KHCN₂ melamine has been reacted with potassium amide in liquid ammonia. After evaporation of the solvent the resulting solid has been transformed at 210°C. KHCN₂ (P2₁2₁2₁, a = 708.7(2), b = 909.0(2), c = 901.4(2) pm, Z = 8, R = 0.039, wR = 0.016) is yielded as a coarse crystalline product. In the solid K⁺ and HCN ions occur. As expected two significantly differing bond-distances C? N (117.3(5) pm) and HN? C (128.7(5) pm) have been found in the anion. According to IR-spectroscopy a non linear group N? C? N (174.4(4)°) is observed.     

Darstellung und Kristallstruktur von LnAl3Br12 (Ln = La,Ce, Pr,Nd, Sm,Gd) und thermischer Abbau zu LnBr3

Preparation and Crystal Structure of LnAl₃Br₁₂ (Ln = La, Ce, Pr, Nd, Sm, Gd) and Thermal Decomposition to LnBr₃ LnAl₃Br₁₂ (Ln = La, Ce, Pr, Nd, Sm, Gd) was prepared in crystalline form for the first time. The crystal structures of LaAl₃Br₁₂, PrAl₃Br₁₂, and NdAl₃Br₁₂ were determined on single crystals by X-ray methods. The isotypic compounds crystallize with trigonal symmetry, space group P 3₁12, Z = 3. A structural comparison to lanthanoide chloroaluminates of equal composition is given and thermal decomposition of LnAl₃Br₁₂ (Ln = Nd) to the corresponding lanthanoide tribromide is described.     

Darstellung,Eigenschaften und Kristallstruktur von Na3[Yb(NH2)6]

Preparation, properties, and crystal structure of Na₃[Yb(NH₂)₆] Na₃[Yb(NH₂)₆] was prepared by the reaction of Na and Yb in the atomic ration 3:1 with ammonia at 150°C and 200 atm as a light grey microcrystalline powder. Colourless single crystals were obtained at 180°C and ～6000 atm. It decomposes rapidly at temperature above 140°C. At 250°C NaNH₂ nd a nitride phase results which crystallizes in the Nacl lattice type with a = 4.86 Å. Na₃[Yb(NH₂)₆] crystallizes orthorhombically with the lattice spacings a = 6.492 Å, b = 12.24 Å, and c = 21.33 Å with 8 formula units per unit cell. The space group is D–Pbca (No.61). The amide ions have a distorted close-packed arrangement with the layer sequence ABAC in the direction [010]. Ytterbium occupies on sixth, sodium one half of the octahedral interstices.     

Das System KCl/ErCl3 und die Modifikationen der Verbindungen K3LnCl6 (Ln = Ce–Lu,Y)

The System KCl/ErCl₃ and the Modifications of Compounds K₃LnCl₆ (Ln = Ce–Lu, Y) The phase diagram of the system KCl/ErCl₃ was investigated by DTA and XRD. Two compounds exist: KEr₂Cl₇ incongruently and K₃ErCl₆ congruently melting. Their thermodynamic functions for the formation from KCl and ErCl₃ were determined by solution calorimetry and emf vs T measurements in a galvanic cell for solid electrolytes. Both compounds are stable down to 0 K. – K₃ErCl₃ exists in three modifications. The structure of T–K₃ErCl₆ was determined by single crystal measurements: S.G. P2₁/c; Z = 4; a = 1309.8(5), b = 767.1(3), c = 1252.6(4) pm, β = 109.94(2)°. – A survey of all known results on compounds K₃LnCl₆ reveals, that from Ln = Ce to Ln = Ho they only are stable at higher temperatures, > 521 °C (Ce) and > –27 °C (Ho), resp.     

Darstellung,Kristallstruktur und Eigenschaften von Cäsiumozonid

Synthesis, Crystal Structure and Properties of Cesium Ozonide By reaction between CsO₂ and mixtures of O₂ and O₃ in the temperature range from 25°C to ?70°C and subsequent extraction with liquid ammonia pure CsO₃ was obtained in grammeamounts. By X-ray powder and thermal techniques a reversible, structural phase transition was detected at +8°C, and decomposition into CsO₂ and O₂ at +53°C. The low-temperature form (T? CsO₃) is isostructural to RbO₃ (P2₁/c; a = 675.1(2), c = 901.5(3) pm, β = 120.74(3)°l Z = 4), the crystal structure of H? CsO₃, which shows orientational disorder with respect to the ozonide ion, corresponds to the CsCl-type of structure (a = 436.06(3) pm). Using the geometry as determined for KO₃ and RbO₃, and the vibrational frequencies of different isotopomeres, the force constants of O₃^? have been redetermined.     

New Ternary Phosphides Ln25Ni49P33 (Ln = Ce,Pr, Nd,Sm, Gd,Tb, Dy,Ho, Er)

New ternary phosphides Ln₂₅Ni₄₉P₃₃ (Ln = Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) have been synthesized by arc melting of pure components. Crystal structure has been determined for Sm₂₅Ni₄₉P₃₃ using X‐ray powder diffraction data and the Rietvelt method: P6m2, a = 22.096(4), c = 3.8734(9) Å, R = 0.096. Crystal structure of Sm₂₅Ni₄₉P₃₃ is of a new type and belongs to large family of ternary compounds with trigonal‐prismatic coordination of the smallest size atoms and metal to nonmetal ratio equal or close to 2 : 1. It is a member of homologous subseries of the compounds with unit cell contents described by general chemical formula R M X . Lattice parameters of the isotypic compounds Ln₂₅Ni₄₉P₃₃ have been refined using X‐ray powder diffraction data.     

Synthese,Kristallstruktur und magnetische Eigenschaften von TbAl3Cl12

Synthesis, Crystal Structure, and Magnetic Properties of TbAl₃Cl₁₂ TbAl₃Cl₁₂ was synthesized and the crystal structure was determined from single crystal X‐ray diffraction data for the first time. The compound crystallizes trigonally in space group P3₁12 with a = 1049.8(1) and c = 1567.3(2) pm. Terbium cations are located in quadratic antiprisms of chloride anions. Magnetic measurements were performed to study the interactions between Tb³⁺ and Cl^–. Magnetic data were interpreted by ligand field calculations applying the angular overlap model.     

Sm2Si3O3N4 und Ln2Si2,5Al0,5O3,5N3,5 (Ln = Ce,Pr, Nd,Sm, Gd) – neuer synthetischer Zugang zu N‐haltigen Melilith‐Phasen und deren Einkristall‐Röntgenstrukturanalyse

Sm₂Si₃O₃N₄ and Ln₂Si_2.5Al_0.5O_3.5N_3.5 (Ln = Ce, Pr, Nd, Sm, Gd) – A Novel Synthetic Approach for the Preparation of N‐containing Melilites and X‐Ray Single‐Crystal Structure Determination The high‐temperature synthesis of nitridosilicates using an especially developed rf furnace was now transferred to the preparation of single‐crystalline oxonitridosilicates and oxonitridoaluminosilicates (sialons). Sm₂Si₃O₃N₄ was obtained by the reaction of SrCO₃, Si(NH)₂, and the respective lanthanoides, for Ln₂Si_2.5Al_0.5O_3.5N_3.5 (Ln = Ce, Pr, Nd, Sm, Gd) additionally AlN was used. The compounds were obtained as coarsely crystalline products. Their crystal structures were refined on the basis of single‐crystal X‐ray diffraction data. Sm₂Si₃O₃N₄ (a = 768.89(4), c = 499.60(4) pm) and the isotypic sialons Ce₂Si_2.5Al_0.5O_3.5N_3.5 (a = 779.20(3), c = 506.94(4) pm), Pr₂Si_2.5Al_0.5O_3.5N_3.5 (a = 778.26(4), c = 508.56(5) pm), Nd₂Si_2.5Al_0.5O_3.5N_3.5 (a = 776.15(4), c = 506.7(3) pm), Sm₂Si_2.5Al_0.5O_3.5N_3.5 (a = 772.63(13), c = 502.80(9) pm), and Gd₂Si_2.5Al_0.5O_3.5N_3.5 (a = 774.15(5), c = 506.46(4) pm) are new representatives of the N‐containing melilite structure type (space group P 4 2₁m (no. 113), Z = 2). For the structure analysis specific models were applied, which have been developed by Werner et al. on the basis of powder diffraction data.     

Synthese,Kristallstrukturen und thermisches Verhalten von Er2(SO4)3 · 8 H2O und Er2(SO4)3 · 4 H2O

Syntheses, Crystal Structures, and Thermal Behavior of Er₂(SO₄)₃ · 8 H₂O and Er₂(SO₄)₃ · 4 H₂O Evaporation of aqueous solutions of Er₂(SO₄)₃ yields light pink single crystals of Er₂(SO₄)₃ · 8 H₂O. X-ray single crystal investigations show that the compound crystallizes monoclinically (C2/c, Z = 8, a = 1346.1(3), b = 667.21(1), c = 1816.2(6) pm, β = 101.90(3)°, R_all = 0.0169) with eightfold coordination of Er³⁺, according to Er(SO₄)₄(H₂O)₄. DSC- and temperature dependent X-ray powder investigations show that the decomposition of the hydrate follows a two step mechanism, firstly yielding Er₂(SO₄)₃ · 3 H₂O and finally Er₂(SO₄)₃. Attempts to synthesize Er₂(SO₄)₃ · 3 H₂O led to another hydrate, Er₂(SO₄)₃ · 4 H₂O. There are two crystallographically different Er³⁺ ions in the triclinic structure (P 1, Z = 2, a = 663.5(2), b = 905.5(2), c = 1046.5(2) pm, α = 93.59(3)°, β = 107.18(2)°, γ = 99.12(3)°, R_all = 0.0248). Er(1)³⁺ is coordinated by five SO₄^2– groups and three H₂O molecules, Er(2)³⁺ is surrounded by six SO₄^2– groups and one H₂O molecule. The thermal decomposition of the tetrahydrate yields Er₂(SO₄)₃ in a one step process. In both cases the dehydration produces the anhydrous sulfate in a modification different from the one known so far.     

Darstellung,Eigenschaften und Kristallstruktur von Bis(phthalocyaninato)cer(IV)

Preparation, Properties and Crystal Structure of Bis(phthalocyaninato)cerium(IV) The anodic or chemical oxidation with dibenzoylperoxide of solutions of bis(phthalocyaninato)cerate(III) in dichloromethane yields selectively sparely soluble bis(phthalocyaninato)cerium(IV), [Ce(Pc(2-)) 2 ]. Green, monoclinic needles cristallize with a = 18.783(12) Å b = 18.739(16) Å c= 15.618(10) Å ß114.30(7)°; Z = 4; space group C2/c. [Ce(Pc(2–)) 2 ] is a sandwich complex in which the cerium Atom is eightfold coordinated by the isoindole nitrogens of the two staggered convex Pc-rings. The u.v.-vis., m.i.r., f.i.r. and resonance Raman spectra are consistent with the structure.     

Darstellung,Kristallstruktur und Eigenschaften von KLi2As

Preparation, Crystal Structure, and Properties of KLi₂As The novel arsenide KLi₂As has been synthesized either from the elements or from mixtures of the binary components Li₃As and K₃As in sealed Nb ampoules at 823 K and 623 K, respectively. It crystallizes in the space group Pmmn (no. 59) with a = 445.8(9); b = 671.5(11); c = 627.0(12) pm and Z = 2 formula units. The metallic reflecting silvercoloured platelets hydrolize rapidly under wet air. The compound (Pearson code oP8) is isopuntal with BaLi₂Si and an intermediate between the Li₃N and the Na₃As type of structure. Potassium is distorted tetrahedrally coordinated by four As atoms (d(K? As) = 355 and 367 pm), arsenic by four potassium and six lithium atoms (d(As? K) = 355–367 pm; d(As? Li) = 260–265 pm) in form of a sphenocorona. Lithium is threefold coordinated (distorted trigonal planar) by arsenic and this unit is enveloped by a monocapped trigonal prism build by three lithium and four potassium atoms.     

Synthese und Struktur der Nitridoborat‐Nitride Ln4(B2N4)N (Ln = La,Ce) des Formeltyps Ln3+x(B2N4)Nx (x = 0, 1, 2)

Synthesis and Structure of Nitridoborate Nitrides Ln₄(B₂N₄)N (Ln = La, Ce) of the Formula Type Ln_3+x(B₂N₄)N_x (x = 0, 1, 2) The missing member of the formula type Ln_3+x(B₂N₄)N_x with x = 1 was synthesized and characterized for Ln = La and Ce. According to the single‐crystal X‐ray structure solution Ce₄(B₂N₄)N crystallizes in the space group C2/m (Z = 2) with the lattice parameters a = 1238.2(1) pm, b = 357.32(3) pm, c = 905.21(7) pm and β = 129.700(1)°. The anisotropic structure refinement converged at R1 = 0.039 and wR2 = 0.099 for all independent reflections. A powder pattern of La₄(B₂N₄)N was indexed isotypically with a = 1260.4(1) pm, b = 366.15(3) pm, c = 919.8(1) pm and β = 129.727(6)°. A structure rational for nitridoborates and nitridoborate nitrides containing B₂N₄ ions with the general formula Ln_3+x(B₂N₄)N_x with x = 0, 1, 2 is presented.