03 Fakultät Chemie

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/4

Browse

Search Results

Now showing 1 - 10 of 51
  • Thumbnail Image
    ItemOpen Access
    The crystal structures of two hydro-closo-borates with divalent tin in comparison : Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O
    (2021) Kleeberg, Fabian M.; Zimmermann, Lucas W.; Schleid, Thomas
    Single crystals of Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O are easily accessible by reactions of aqueous solutions of the acids (H3O)2[B10H10] and (H3O)2[B12H12] with an excess of tin metal powder after isothermal evaporation of the clear brines. Both compounds crystallize with similar structures in the triclinic system with space group P1¯ and Z = 2. The crystallographic main features are electroneutral 1∞{Sn(H2O)3/1[B10H10]3/3} and 1∞{ Sn(H2O)3/1[B12H12]3/3} double chains running along the a-axes. Each Sn2+ cation is coordinated by three water molecules of hydration (d(Sn-O) = 221-225 pm for the B10 and d(Sn-O) = 222-227 pm for the B12 compound) and additionally by hydridic hydrogen atoms of the three nearest boron clusters (d(Sn-H) = 281-322 pm for the B10 and d(Sn-H) = 278-291 pm for the B12 compound), which complete the coordination sphere. Between these tin(II)-bonded water and the three or four interstitial crystal water molecules, classical bridging hydrogen bonds are found, connecting the double chains to each other. Furthermore, there is also non-classical hydrogen bonding between the anionic [BnHn]2- (n = 10 and 12) clusters and the crystal water molecules pursuant to B-Hδ-⋯δ+H-O interactions often called dihydrogen bonds.
  • Thumbnail Image
    ItemOpen Access
    Scheelite-type sodium neodymium(III) ortho-oxidomolybdate(VI), NaNd[MoO4]2
    (2011) Schleid, Thomas; Hartenbach, Ingo
    The crystal structure of Scheelite-type NaNd[MoO4]2 is described in the paper.
  • Thumbnail Image
    ItemOpen Access
    Crystal structure of trirubidium dodekaselenoheptadysprosate(III), Rb3Dy7Se12
    (2000) Folchnandt, Matthias; Schleid, Thomas
    Dy7Rb3Se12, orthorhombic, Pnnm (No. 58), a = 12.590(1) Å, b = 26.183(2) Å, с = 4.1271(4) Å, V= 1360.5 Å 3 , Z = 2, Rgt(F) = 0.054, wR(F2) = 0.119, Τ = 293 К.
  • Thumbnail Image
    ItemOpen Access
    New crystal structures of rare‐earth metal(III) oxotellurates(IV) RE2Te3O9: A1‐type (RE=La, Ce) and A2‐type (RE=Pr, Nd)
    (2021) Chou, Sheng‐Chun; Höss, Patrick; Russ, Philip L.; Strobel, Sabine; Schleid, Thomas
    The new rare-earth metal(III) oxotellurates(IV) RE2Te3O9 (RE=La-Nd) of the so far unknown A-type structure can be obtained as needle-shaped single crystals through solid-state reactions of the corresponding binary oxides. Their crystal structures were determined as A1-type for RE=La and Ce or A2-type for RE=Pr and Nd by single-crystal X-ray diffraction. Both structure types crystallize in the monoclinic crystal system, but in two different non-centrosymmetric space groups: the A1-type with Z=8 in space group P21 (La2Te3O9: a=569.54(3), b=2230.12(13), c=1464.71(4) pm, β=101.205(3)°; Ce2Te3O9: a=567.02(3), b=2222.61(13), c=1457.13(9) pm, β=101.134(3)°) or the A2-type with Z=16 in space group Cc (Pr2Te3O9: a=2838.61(16), b=563.89(3), c=2522.08(15) pm, β=118.816(3)°; Nd2Te3O9: a=2826.38(16), b=561.47(3), c=2511.94(15) pm, β=118.841(3)°). In spite of the differences in the unit-cell parameters and the symmetry, both structures consist of quite similar fundamental building blocks (FBBs) consisting of eight crystallographically distinct rare-earth metal-oxygen polyhedra with C.N.(RE3+) from seven to nine and always twelve different ψ1-tetrahedral oxotellurate(IV) anions [TeO3]2-, which show a high number of secondary bonding interactions (SBIs) with each other in all four cases.
  • Thumbnail Image
    ItemOpen Access
    Synthesis, crystal structure and properties of the new laminar quaternary tellurides SrLnCuTe3 (Ln = Sm, Gd-Tm and Lu)
    (2023) Ruseikina, Anna V.; Grigoriev, Maxim V.; Molokeev, Maxim S.; Garmonov, Alexander A.; Elyshev, Andrey V.; Locke, Ralf J. C.; Schleid, Thomas
    This paper reports for the first time on the new laminar quaternary orthorhombic heterometallic quaternary tellurides SrLnCuTe3, the fabrication of which has been a challenge until this work. Data on the crystal structure of tellurides complete the series of quaternary strontium chalcogenides SrLnCuCh3 (Ch = S, Se, Te). Single crystals of the compounds were synthesized from the elements by the halogenide-flux method at 1070 K. The compounds are crystallizing in two space groups Pnma (Ln = Sm, Gd and Tb) and Cmcm (Ln = Dy-Tm and Lu). For SrSmCuTe3 (a = 11.4592(7), b = 4.3706(3), c = 14.4425(9) Å, space group: Pnma) with the largest lanthanoid cation, Sr2+ shows C.N. = 7, whereas Sm3+ reveals a diminished coordination number C.N. = 6. For SrLuCuTe3 (a = 4.3064(3), b = 14.3879(9), c = 11.1408(7) Å, space group: Cmcm) with the smallest lanthanoid cation, coordination numbers of six are realized for both high-charged cations (Sr2+ and Lu3+: C.N. = 6). The cations Sr2+, Ln3+, Cu+ each take independent positions. The structures are built by distorted [CuTe4]7- tetrahedra, forming the infinite chains {∞1[Cu(Te1)1/1t(Te2)1/1t(Te3)2/2e]5−} along [010] in SrLnCuTe3 (Ln = Sm, Gd and Tb) and [100] in SrLnCuTe3 (Ln = Dy-Tm and Lu). The distortion of the polyhedra [CuTe4]7- was compared for the whole series SrLnCuTe3 by means of τ4-descriptor for the four coordinating Te2- anions, which revealed a decrease in the degree of distortion with a decreasing radius at Ln3+. The distorted octahedra [LnTe6]9- form layers {∞2[Ln(Te1)2/2(Te2)2/2(Te3)2/2]3−}. The distorted octahedra and tetrahedra fuse to form parallel layers {∞2[CuLnTe3]2−} and between them, the Sr2+ cations providing three-dimensionality of the structure are located. In the SrLnCuTe3 (Ln = Sm, Gd and Tb) structures, the Sr2+ cations center capped the trigonal prisms [SrTe6+1]12−, united in infinite chains {∞1[Sr(Te1)2/2(Te2)3/3(Te3)2/2]4−} along the [100] direction. The domains of existence of the Ba2MnS3, BaLaCuS3, Eu2CuS3 and KZrCuS3 structure types are defined in the series of orthorhombic chalcogenides SrLnCuCh3 (Ch = S, Se and Te). The tellurides SrLnCuTe3 (Ln = Tb-Er) of both structure types in the temperature range from 2 up to 300 K are paramagnetic, without showing clear signs of a magnetic phase transition.
  • Thumbnail Image
    ItemOpen Access
    The first members of the monoclinic lanthanoid(III) fluoride oxoarsenate(III) series Ln2F2[As2O5] (Ln=La - Nd and Sm)
    (2025) Locke, Ralf J. C.; Zimmer, Frank C.; Schleid, Thomas
    In synthesis experiments for the preparation of Ln5F3[AsO3]4 representatives in evacuated glassy silica ampoules at temperatures of maximum 825 °C, surprisingly compounds with the composition Ln2F2[As2O5] could be obtained and subsequently also reproduced on target. The new Ln2F2[As2O5] representatives with Ln = La - Nd and Sm crystallize needle‐shaped in the monoclinic space group P21/c with lattice parameters ranging from a = 793.24(5) pm, b = 1346.39(9) pm, c = 1359.41(9) pm and β = 106.932(3)° for La2F2[As2O5] to a = 769.11(5) pm, b = 1307.50(9) pm, c = 1328.74(9) pm and β = 106.819(3)° for Sm2F2[As2O5] with Z = 8. Their crystal structure can be broken down into two parts consisting of infinite [Ln2F2]4+ and discrete [As2O5]4− units. Three distinct kinds of fluoride anions are trigonally planar surrounded by lanthanoid cations and another one carries even a fourth of them in their coordination sphere with a secondary contact resulting in a distorted tetrahedron. These [FLn3]8+ and [FLn3+1]11+ building blocks share common corners and edges creating strands {[F2Ln2]4+}, which propagate along [100]. The four different As3+ lone‐pair cations form ψ1‐tetrahedra [AsO3]3− with three oxygen atoms and are conversurally linked pairwisely creating dinuclear pyroanionic [As2O5]4− units. These [As2O5]4− groups arrange themselves alternatingly along [100] with their lone pairs pointing into central empty channels. The {[F2Ln2]4+} strands are linked to the [As2O5]4− units via four distinguishable Ln3+ cations providing them coordination numbers of eight and nine. Raman spectroscopy confirmed that no (OH)− groups resulting from the synthesis were present apt to replace part of the F− and the stoichiometry Ln2F2[As2O5] was verified using WDXS elemental analyses.
  • Thumbnail Image
    ItemOpen Access
    Synthesis and crystal‐structure analysis of the K2NiF4‐type hydride oxides LiLnEuH2-xO2 (Ln=La, Ce, Pr, Nd, Sm) and LiEu2H3O by neutron and X‐ray diffraction
    (2022) Hoslauer, Jean‐Louis; Zapp, Nicolas; Fischer, Henry E.; Rudolph, Daniel; Kohlmann, Holger; Schleid, Thomas
    The hydride oxides LiLnEuH2-xO2 (Ln=La, Ce, Pr, Nd and Sm) were synthesized by reaction of the lanthanide sesquioxides with europium monoxide, europium dihydride and lithium hydride under inert conditions at 750 °C as black powders. They crystallize in the tetragonal K2NiF4‐type structure (space group: I4/mmm) with a mixed Ln3+/Eu2+ occupation. The crystal structures of the europium representatives LiLaEuH2-xO2 and LiLaEuD2-xO2 were analyzed by powder neutron diffraction data at short wavelengths (λ=70 pm). Hydrogen (deuterium) and oxygen atoms occupy distinct crystallographic sites with considerable vacancy concentrations on the hydrogen positions (a=363.80(8) pm, c=1323.3(3) pm, c/a=3.637 for LiLaEuH1.26(4)O2 and a=363.43(5) pm, c=1321.6(2) pm, c/a=3.636 for LiLaEuD1.41(2)O2). Moving from the mixed Ln/Eu occupation in LiLnEuH2O2 to Ln=Eu2+, we obtained the mixed‐anionic phase LiEu2H3O, which crystallizes in the same structure type with a=370.04(2) pm, c=1317.32(8) pm and c/a=3.560.
  • Thumbnail Image
    ItemOpen Access
    The triclinic lanthanoid(III) halide oxidoarsenates(III) Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3]
    (2020) Goerigk, Felix C.; Schander, Svetlana; Wickleder, Mathias S.; Schleid, Thomas
    Pale yellow single crystals of the composition Ln3X2[As2O5][AsO3] (Ln = Tm for X = Br and Ln = Sm for X = Cl) were obtained via solid‐state reactions in the systems Ln2O3/As2O3 from sealed silica ampoules using different halides as fluxing agents. Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3] crystallize isotypically in the triclinic space group P1 with Z = 2 and cell parameters of a = 543.51(4) pm, b = 837.24(6) pm, c = 1113.45(8) pm, α = 90.084(2)°, β = 94.532(2)°, γ = 90.487(2)° for the samarium and a = 534.96(4) pm, b = 869.26(6) pm, c = 1081.84(8) pm, α = 90.723(2)°, β = 94.792(2)° γ = 90.119(2)° for the thulium compound. The isotypic crystal structure of both representatives exhibits three crystallographically different Ln3+ cations, each with a coordination number of eight. (Ln1)3+ and (Ln2)3+ are only coordinated by three oxygen atoms, whereas (Ln3)3+ shows additional contacts to halide anions in forming square [LnO4X4]9- antiprisms. All As3+ cations are surrounded by three oxygen atoms in the shape of isolated [AsO3]3- ψ1‐tetrahedra. They occur either isolated or condensed as pyroanionic [As2O5]4- units with a bridging oxygen atom. In both anions, non‐binding lone‐pair electrons are present at the As3+ cations with a pronounced stereochemically active function.
  • Thumbnail Image
    ItemOpen Access
    Crystal structure of hexapraseodymium(III) trinitride tetrasulfide chloride, Pr6N3S4Cl
    (1999) Meyer, M.; Schleid, Thomas
    ClN3Pr6S4, orthorhombic, Pnma (No. 62), a = 11.3987(8) Å, b = 4.0235(3) Å, c = 26.999(1) Å, V = 1238.3 Å3 ,Z = 4, Rgt{F) = 0.037, Rw(F2) = 0.079, T = 293 Κ.
  • Thumbnail Image
    ItemOpen Access
    Sulfur‐composites derived from poly(acrylonitrile) and poly(vinylacetylene) : a comparative study on the role of pyridinic and thioamidic nitrogen
    (2023) Kappler, Julian; Klostermann, Sina V.; Lange, Pia L.; Dyballa, Michael; Veith, Lothar; Schleid, Thomas; Weil, Tanja; Kästner, Johannes; Buchmeiser, Michael R.
    Sulfurized poly(acrylonitrile) (SPAN) is a prominent example of a highly cycle stable and rate capable sulfur/polymer composite, which is solely based on covalently bound sulfur. However, so far no in‐depth study on the influence of nitrogen in the carbonaceous backbone, to which sulfur in the form of thioketones and poly(sulfides) is attached, exists. Herein, we investigated the role of nitrogen by comparing sulfur/polymer composites derived from nitrogen‐containing poly(acrylonitrile) (PAN) and nitrogen‐free poly(vinylacetylene) (PVac). Results strongly indicate the importance of a nitrogen‐rich, aromatic carbon backbone to ensure full addressability of the polymer‐bound sulfur and its reversible binding to the aromatic backbone, even at high current rates. This study also presents key structures, which are crucial for highly cycle and rate stable S‐composites.