ζ-Y2[Si2O7]: Ein neuer Strukturtyp in der Yttrialit-Reihe / ζ -Y2[Si2O7]: A New Structure Type within the Yttrialite Series

2006 ◽  
Vol 61 (9) ◽  
pp. 1054-1060 ◽  
Author(s):  
Ingo Hartenbach ◽  
Steffen F. Meier ◽  
Thomas Schleid
Keyword(s):  
Single Crystals ◽  
Title Compound ◽  
Structure Type ◽  
Unit Cell ◽  
Type Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vertex Sharing ◽  
A Minor ◽  
Oxygen Atoms

Abstract During attempts of preparing yttrium oxotellurates(IV) using Y2O3 and TeO2 in YCl3 fluxes, the occasional reaction of these educts with the walls of the evacuated silica ampoules led to colourless, lath-shaped single crystals of Y2[Si2O7] in the new ζ -type structure as a minor by-product which was investigated by X-ray diffraction. The title compound crystallizes monoclinically in the space group P21/m (a = 503.59(5), b = 806.47(8), c = 732.65(7) pm, β = 108.633(6)°) with two formula units per unit cell. The crystallographically unique Y3+ cation is coordinated by seven oxygen atoms (d(Y-O = 221 - 248 pm) arranged in the shape of a slightly distorted monocapped octahedron. The isolated oxodisilicate units [Si2O7]6− consist of two Si4+ cations and seven O2− anions of which five are crystallographically independent. These pyroanions (d(Si-O) = 161 - 168 pm, ∢ (O-Si-O) = 91 - 117°, ∢ (Si-O-Si) = 156°) exhibit an almost perfectly eclipsed conformation built of a horseshoeshaped backbone with the two silicon and three of the oxygen atoms situated on the mirror planes of the unit cell. The remaining four oxide anions complete this [Si2O7]6− entity of two vertex-sharing [SiO4]4− tetrahedra as terminal ligands for silicon. Assembled in planar layers parallel to (−1 0 1), the [Si2O7]6− anions are packed with their wide basal faces of the tetrahedra pointing towards the small waist of the adjacent units and vice versa. The yttrium cations reside between these layers in order to interconnect them three-dimensionally.

EuPdGe - a New Germanide with EuNiGe Type Structure

1995 ◽  
Vol 50 (8) ◽  
pp. 1181-1184 ◽  
Author(s):  
Rainer Pöttgen
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Title Compound ◽  
Type Structure ◽  
X Ray Diffraction ◽  
X Ray

The title compound was prepared from the elemental components in a tantalum tube at 1070 K and investigated by X-ray diffraction of both powder as well as single crystals. The crystal structure was refined from four-circle diffractometer data: P21/n, a = 618.1(1), b = 613.6(1), c = 743.9(1) pm, β = 109.40(1)°, V = 0.2661(1) nm3, Z = 4, wR2 = 0.0536 for 1564 F2 values and 29 variables. EuPdGe crystallizes with the EuNiGe type structure. Both Pd and Ge atoms in EuPdGe have three germanium or palladium neighbors, respectively. They form two-dimensionally infinite [PdGe] polyanions which consist of corrugated 4.82 nets. These polyanions are separated by the europium atoms.

A new stacking variant of Na2Pt(OH)6

2018 ◽  
Vol 73 (11) ◽  
pp. 831-836 ◽  
Author(s):  
Gohil S. Thakur ◽  
Hans Reuter ◽  
Claudia Felser ◽  
Martin Jansen
Keyword(s):  
Oxygen Pressure ◽  
Title Compound ◽  
Structure Type ◽  
Direct Reaction ◽  
Solid Residue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Edge Distance ◽  
Naoh Solution

AbstractA new stacking variant of sodium hexa-hydroxo platinate(IV), Na2Pt(OH)6, was synthesized and its structure elucidated through X-ray diffraction. The new polymorph was prepared by direct reaction of PtO2 with an excess of NaOH solution applying elevated oxygen pressure at 300°C. The structure consists of layers of edge sharing Pt(OH)6 and Na(OH)6 octahedra. These layers are separated by an edge-to-edge distance of ~2.4 Å. The packing of the hydroxide ions corresponds to the hcp sequence, the title compound thus may be regarded a cation ordered variant of the Brucite structure type. During heating above T~300°C all constitutional water is released, and anhydrous Na2PtO3 remains as the solid residue.

scholarly journals Rubidium tetrafluoridobromate(III): redetermination of the crystal structure from single-crystal X-ray diffraction data

IUCrData ◽  
2019 ◽  
Vol 4 (11) ◽  
Author(s):  
Artem V. Malin ◽  
Sergei I. Ivlev ◽  
Roman V. Ostvald ◽  
Florian Kraus
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Square Planar ◽  
Atomic Coordinates

Single crystals of rubidium tetrafluoridobromate(III), RbBrF4, were grown by melting and recrystallizing RbBrF4 from its melt. This is the first determination of the crystal structure of RbBrF4 using single-crystal X-ray diffraction data. We confirmed that the structure contains square-planar [BrF4]− anions and rubidium cations that are coordinated by F atoms in a square-antiprismatic manner. The compound crystallizes in the KBrF4 structure type. Atomic coordinates and bond lengths and angles were determined with higher precision than in a previous report based on powder X-ray diffraction data [Ivlev et al. (2015). Z. Anorg. Allg. Chem. 641, 2593–2598].

The solid solution TbNiIn1−x Ga x

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Myroslava Horiacha ◽  
Galyna Nychyporuk ◽  
Rainer Pöttgen ◽  
Vasyl Zaremba
Keyword(s):  
Solid Solution ◽  
Unit Cell ◽  
Type Structure ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Structure Space ◽  
Arc Melting

Abstract Phase formation in the solid solution TbNiIn1−x Ga x at 873 K was investigated in the full concentration range by means of powder X-ray diffraction and EDX analysis. The samples were synthesized by arc-melting of the pure metals with subsequent annealing at 873 K for one month. The influence of the substitution of indium by gallium on the type of structure and solubility was studied. The solubility ranges have been determined and changes of the unit cell parameters were calculated on the basis of powder X-ray diffraction data: TbNiIn1–0.4Ga0–0.6 (ZrNiAl-type structure, space group P 6 ‾ 2 m $P‾{6}2m$ , a = 0.74461(8)–0.72711(17) and c = 0.37976(5)–0.37469(8) nm); TbNiIn0.2–0Ga0.8–1.0 (TiNiSi-type structure, space group Pnma, а = 0.68950(11)–0.68830(12), b = 0.43053(9)–0.42974(6), с = 0.74186(10)–0.73486(13) nm). The crystal structures of TbNiGa (TiNiSi type, Pnma, a = 0.69140(5), b = 0.43047(7), c = 0.73553(8) nm, wR2=0.0414, 525 F 2 values, 21 variables), TbNiIn0.83(1)Ga0.17(1) (ZrNiAl type, P 6 ‾ 2 m $P‾{6}2m$ , a = 0.74043(6), c = 0.37789(3) nm, wR2 = 0.0293, 322 F 2 values, 16 variables) and TbNiIn0.12(2)Ga0.88(2) (TiNiSi type, Pnma, a = 0.69124(6), b = 0.43134(9), c = 0.74232(11) nm, wR2 = 0.0495, 516 F 2 values, 21 variables) have been determined. The characteristics of the solid solutions and the variations of the unit cell parameters are briefly discussed.

Copper deficiency in UCu5−x Sn [x = 0.37 (1)]

2006 ◽  
Vol 62 (4) ◽  
pp. i106-i108
Author(s):  
Svilen Bobev ◽  
Eric D. Bauer ◽  
John L. Sarrao
Keyword(s):  
Single Crystal ◽  
Title Compound ◽  
Copper Deficiency ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phase Width

The ternary intermetallic title compound, known hitherto as UCu5Sn (uranium pentacopper stannide), crystallizes with the hexagonal CeNi5Sn structure type, and it has been presumed to be a fully stoichiometric phase, devoid of any disorder. However, the present single-crystal X-ray diffraction studies at 120 K, carried out with crystals grown from an Sn flux, suggest the existence of a previously unnoticed phase width of the title compound UCu5−x Sn. All the atoms occupy special positions: U (\overline{6}m2, \overline{3}m.), Sn (3m.) and Cu (.m., 3m., and two positions with \overline{6}m2).

Crystal and Molecular Structure of 3-Iodo-2-propynyl-N-butylcarbamate

1997 ◽  
Vol 52 (2) ◽  
pp. 256-258 ◽  
Author(s):  
Evgeni V. Avtomonov ◽  
Rainer Grüning ◽  
Jörg Lorberth
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Network ◽  
Carbamate Group ◽  
Oxygen Atoms

Abstract The crystal structure of the title compound has been determined by X-ray diffraction methods. Due to the Lewis acidic character of the iodine substituent a “zig-zag” chain is formed via intermolecular interactions (2.933(4) A) between iodine and oxygen atoms of theocarbamate moiety. A three-dimensional network is formed through hydrogen-bridging (2.04 A) between NH-groups and the oxygen atoms of the neighbouring carbamate group of the next molecule.

scholarly journals Diterbium heptanickel: a crystal structure redetermination

2014 ◽  
Vol 70 (8) ◽  
pp. i42-i42
Author(s):  
Volodymyr Levytskyy ◽  
Volodymyr Babizhetskyy ◽  
Bohdan Kotur ◽  
Volodymyr Smetana
Keyword(s):  
Crystal Structure ◽  
Diffraction Data ◽  
Title Compound ◽  
Stoichiometric Composition ◽  
Structure Type ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Coordination Polyhedra ◽  
X Ray ◽  
Anisotropic Displacement Parameters

The crystal structure of the title compound, Tb2Ni7, was redetermined from single-crystal X-ray diffraction data. In comparison with previous studies based on powder X-ray diffraction data [Lemaireet al.(1967).C. R. Acad. Sci. Ser. B,265, 1280–1282; Lemaire & Paccard (1969).Bull. Soc. Fr. Mineral. Cristallogr.92, 9–16; Buschow & van der Goot (1970).J. Less-Common Met.22, 419–428], the present redetermination affords refined coordinates and anisotropic displacement parameters for all atoms. A partial occupation for one Tb atom results in the non-stoichiometric composition Tb1.962 (4)Ni7. The title compound adopts the Ce2Ni7structure type and can also be derived from the CaCu5structure type as an intergrowth structure. The asymmetric unit contains two Tb sites (both site symmetries 3m.) and five Ni sites (.m.,mm2, 3m., 3m., -3m.). The two different coordination polyhedra of Tb are a Frank–Kasper polyhedron formed by four Tb and 12 Ni atoms and a pseudo Frank–Kasper polyhedron formed by two Tb and 18 Ni atoms. The four different coordination polyhedra of Ni are Frank–Kasper icosahedra formed by five Tb and seven Ni atoms, four Tb and eight Ni atoms, three Tb and nine Ni atoms, and six Tb and six Ni atoms, respectively.

X-ray diffraction analysis of (Na0.6H0.4)(Ta0.7Nb0.3)O3

1999 ◽  
Vol 14 (3) ◽  
pp. 231-233 ◽  
Author(s):  
Raj P. Singh ◽  
Michael J. Miller ◽  
Jeffrey N. Dann
Keyword(s):  
High Temperature ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Unit Cell ◽  
Type Structure ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray

(Na0.6H0.4)(Ta0.7Nb0.3)O3 was synthesized by heating a tantalum/niobium scale containing two sodium tantalate/niobate phases :Na14(Ta0.7Nb0.3)12O37·31H2O and NaH2Ta0.7Nb0.3O4. Powder X-ray diffraction data for (Na0.6H0.4)(Ta0.7Nb0.3)O3 indicated it to be a cubic perovskite (ABO3/ReO3 type structure) with unit cell a0=3.894 Å. The compound is analogous to the mineral lueshite (NaNbO3), and to the high temperature forms of NaTaO3 and NaNbO3. Powder diffraction data for (Na0.6H0.4)(Ta0.7Nb0.3)O3 will be useful in the analysis of synthetic tantalum/niobium concentrates.

Ba3YRu0.73(2)Al1.27(2)O8 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5: New Perovskite Ruthenates with Partial Octahedra Replacement

2007 ◽  
Vol 62 (11) ◽  
pp. 1383-1389 ◽  
Author(s):  
Barbara Schüpp-Niewaa ◽  
Larysa Shlyk ◽  
Yurii Prots ◽  
Gernot Krabbes ◽  
Rainer Niewa
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
Electron Probe Microanalysis ◽  
Perovskite Structure ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
Powder Mixtures ◽  
X Ray ◽  
Vertex Sharing

Dark red single crystals of the new phases Ba3YRu0.73(2)Al1.27(2)O8 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5 have been grown from powder mixtures of BaCO3, Y2O3, Al2O3, and RuO2 . The compositions given in the formulas result from the refinements of the crystal structures based on single crystal X-ray diffraction data (hexagonal P63/mmc (No. 194), Z = 2, Ba3 YRu0.73(2)Al1.27(2)O8: a = 5.871(1), c = 14.633(3) Å , R1 = 0.035, wR2 = 0.069 and Ba5Y2Ru1.52(2)Al1.47(2)O13.5: a = 5.907(1), c = 24.556(5) Å, R1 = 0.057, wR2 = 0.114). Ba3YRu0.73(2)Al1.27(2)O8 crystallizes in a 6H perovskite structure, Ba5Y2Ru1.52(2)Al1.47(2)O13.5 has been characterized as a 10H Perovskite. Due to similar spatial extensions of (Ru2O9) facesharing pairs of octahedra and (Al2O7) vertex-sharing pairs of tetrahedra, both structures show partial mutual substitution of these units. Consequently, the title compounds may be written as Ba3Y(Ru2O9)1−x(Al2O7)x, x = 0.64(1) and Ba5Y2RuO6(Ru2O9)1−x(Al2O7)x, x = 0.74(1). This interpretation is supported by the results of electron probe microanalysis using wavelength-dispersive X-ray spectroscopy. An oxidation state of Ru close to +5 for the (Ru2O9) units, as can be derived from the distances d(Ru-Ru), additionally leads to similar charges of both the (Ru2O9) and the (Al2O7) units.

Crystal structure of Bis(O-ethylxanthato)bis(quinolin-8-olato)tin(IV)

1978 ◽  
Vol 31 (12) ◽  
pp. 2641 ◽  
Author(s):  
CL Raston ◽  
AH White ◽  
G Winter
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Coordination Sphere ◽  
Title Compound ◽  
Point Symmetry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxygen Atoms

The crystal structure of the title compound, [Sn(S2COEt)2(C9H6NO)2], has been determined by single-crystal X-ray diffraction at 298 K and refined by least squares to a residual of 0.049 for 1771 ?observed? reflections. Crystals are monoclinic, P21/n, a 12.21(1), b 24.33(1), c 9.159(7) Ǻ, β 102.12(6)°, Z 4. The environment of the tin atom is six- coordinate: the two coordinating sulfur atoms of the monodentate xanthate ligands lie cis in the coordination sphere [Sn-S, 2.484(4), 2.510(4) Ǻ], and one in turn trans to the two oxine nitrogen atoms [Sn- N, 2.260(8), 2.237(10) Ǻ]. The remaining positions, trans to each other, are occupied by the oxine oxygen atoms [Sn-O, 2.047(7), 2.065(8) Ǻ]. O-Sn-O is 157.0(3)°. The overall point symmetry of the molecule is a good approximation to 2.

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