Darstellung und Struktur der Phase Li5Na2Sn4 / Preparation and Crystal Structure of Li5Na2Sn4

1978 ◽  
Vol 33 (8) ◽  
pp. 823-826 ◽  
Author(s):  
Klaus Volk ◽  
Wiking Müller
Keyword(s):  
Crystal Structure ◽  
Structure Type ◽  
Unit Cell ◽  
The Other ◽  
Space Group ◽  
Alkali Atoms ◽  
Structural Relations

The new compound Li5Na2Sn4 crystallizes trigonally, a = 472.3 ± 1 pm, c = 7178 ± 8 pm, space group R3̅m-D53d. A quarter of the Sn atoms in the unit cell build up a puck­ered net of six-membered rings, another quarter is bound to the net-atoms forming a tetrahedral Sn coordination. The other half of the Sn atoms is ordered in layers of parallel Sn2 pairs. The nets and layers are separated by the alkali atoms. The structural relations to the variants of the W-structure type of compounds in the system Li-Sn and Na-Sn are shown.

The crystal structure of trisodium hexachlororhodate (Na3RhCl6)

2018 ◽  
Vol 33 (1) ◽  
pp. 62-65
Author(s):  
Martin Etter
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Structure Type ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Commercially available trisodium hexachlororhodate (Na3RhCl6) was dehydrated and characterized by laboratory X-ray powder diffraction. The crystal structure is isostructural to the Na3CrCl6 structure type with space group P$\bar 31$c. Unit-cell parameters are a = 6.8116(1) Å, c = 11.9196(2) Å, V = 478.95(2) Å3, and Z = 2.

Crystal structure and powder data of davidite-type La2Ti10.27Ga9.63O38

1999 ◽  
Vol 14 (1) ◽  
pp. 36-41 ◽  
Author(s):  
A. Meden ◽  
D. Kolar ◽  
S. Škapin
Keyword(s):  
Crystal Structure ◽  
Rietveld Refinement ◽  
Structure Type ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Space Group ◽  
Cell Parameters

The structure type of La2Ti10.27Ga9.63O38 was revealed by a search-match using the PDF. A successful Rietveld refinement (Rp=8.9, Rwp=13.3, RB=4.20) confirmed the structure to be rhombohedral (space group R3¯, No. 148) with the refined unit cell parameters a=9.1878(1) Å, α=68.458(1)°, and V=646.374(1) Å3. The structure is compared to other compounds of the davidite type, and the observed and calculated powder data are given.

Crystal structure and topological affinities of magbasite, KBaFe3+Mg7Si8O22(OH)2F6: a trellis structure related to amphibole and carpholite

2014 ◽  
Vol 78 (1) ◽  
pp. 29-45 ◽  
Author(s):  
M. D. Welch ◽  
R. H. Mitchell ◽  
A. R. Kampf ◽  
A. R. Chakhmouradian ◽  
D. Smith ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Carbonatite Complex ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Cell Parameters ◽  
Structural Relations ◽  
Final Agreement

AbstractThe crystal structure of magbasite from the Eldor carbonatite complex, Quebec, Canada, has been determined and indicates that the currently accepted formula should be revised to KBaFe3+Mg7Si8O22(OH)2F6. Magbasite is orthorhombic, space group Cmme (Cmma), with unit-cell parameters a 18.9506(3) Å, b 22.5045(3) Å, c 5.2780(1) Å, V 2250.93(6) Å3 (Z = 4). The structure has been solved and refined to final agreement indices R1 = 0.026, wR2 = 0.052, GooF = 1.116 for a total of 2379 unique reflections, and is a new kind of trellis motif related to amphibole and carpholite topologies. An amphibole-like I-beam ‖(100) of edge-sharing octahedrally-coordinated M(1,2,3) sites, which are filled by Mg, is sandwiched between double-chains of SiO4 tetrahedra ‖c. This I-beam is connected to side-ribbons ‖(010) of edge-sharing (Mg,Fe2+)O4(OH,F)2 and Fe3+O4(OH)2 octahedra to form a tunnelled box or trellis structure very like that of carpholite, for which the I-beams are pyroxene-like. K occupies a tunnel site analogous to the A site of amphibole. Ba occupies a cavity site at the corners where the I-beam and side-ribbon meet, and corresponds to the A site of carpholite. The structural relations between magbasite and carpholite are discussed.

The Crystal Structure of Eu11Sb10

1979 ◽  
Vol 34 (9) ◽  
pp. 1213-1217 ◽  
Author(s):  
R. Schmelczer ◽  
D. Schwarzenbach ◽  
F. Hulliger
Keyword(s):  
Crystal Structure ◽  
Structure Type ◽  
Thermal Parameters ◽  
The Other ◽  
Interatomic Distances ◽  
Space Group ◽  
Type Space ◽  
True Structure

Abstract Eu11Sb10 crystallizes in the tetragonal Ho11Ge10 structure type, space group I4/mmm, with a = 12.325(2), c = 18.024(4) Å; Z = 4. Large thermal parameters of certain atoms and unusual interatomic distances might suggest that the true structure is slightly distorted, but attempts to desymmetrize the structure were unsuccessful. Analogous anomalies occur in most of the other representatives of the Ho11Ge10 type. Eu11Sb10 appears to be metallic. It contains divalent Eu and is antiferromagnetic below TN ≈ 5 K. Other new representatives of the Ho11Ge10 structure type are Sr11Sb10, Sr11Bi10 and Ba11Sb10.

Crystal structure of Sb2Tl7

1977 ◽  
Vol 55 (7) ◽  
pp. 1120-1122 ◽  
Author(s):  
Rolf Stokhuyzen ◽  
Chung Chieh ◽  
William B. Pearson
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structure Type ◽  
Unit Cell ◽  
Space Group ◽  
Single Crystal Study ◽  
The Mean

The single-crystal study of Sb2Tl7 confirms the work of Morral and Westgren. The crystal is cubic with a = 11.618(6) Å and space group of Im3m. There are 54 atoms per unit cell. It is the only known example of this structure type which can be considered as a true superlattice of CsCl. The structure was determined using 106 observed reflections measured on a G.E. XRD-6 diffractometer. The final R and Rw were 0.097 and 0.060, respectively. The Tl–Tl distances range from 3.21 to 3.55 Å and the mean Sb-Tl distance is 3.27 Å. There is no Sb–Sb contact in the structure

scholarly journals The crystal structure of ceruleite, CuAl4[AsO4]2(OH)8(H2O)4, from Cap Garonne, France

2018 ◽  
Vol 82 (1) ◽  
pp. 181-187 ◽  
Author(s):  
Stuart J. Mills ◽  
Andrew G. Christy ◽  
Georges Favreau
Keyword(s):  
Crystal Structure ◽  
Unit Cell ◽  
The Other ◽  
Space Group ◽  
Unique Structure

ABSTRACTThe crystal structure of ceruleite, CuAl4[AsO4]2(OH)8(H2O)4, has been solved to anR1of 0.0307, using the world's largest crystals from the Cap Garonne mine, France. Ceruleite crystallizes in space groupP21/n, with the unit cella= 7.2000(14),b= 11.345(2),c= 9.856(2) Å, β = 105.57(3)°,V= 775.6(3) Å3andZ= 1. Ceruleite has a unique structure that consists of Al(O,OH)6octahedra that are sharing edges to form rhombus-shaped tetramers. AsO4tetrahedra share two corners with one such rhombus and the other two corners with each of two other rhombi, linking them into a very open mesoporous framework. Cu(OH)2(H2O)2squares lie in the channels and link Al4rhombi along ||b. H2O molecules are also located in the channels.

Über ein neues Kupfervanadat: Cu4V2.15O 9.38 / About Cu4V2,15O9.38

1975 ◽  
Vol 30 (3-4) ◽  
pp. 175-178 ◽  
Author(s):  
H.-P. Christian ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
Hydrothermal Synthesis ◽  
Single Crystals ◽  
Unit Cell ◽  
The Other ◽  
Structure Investigation ◽  
Orthorhombic Unit Cell ◽  
Space Group ◽  
Group D

Single crystals of Cu4V2.15O9,38 were prepared by hydrothermal synthesis. The composition was confirmed by analysis and crystal structure investigation. Cu4V2.15O9,38 has an orthorhombic unit cell : a = 15.021, b = 8.564 and c = 6.055 Å, space group D24P 212121. The structure consists of a network made up of chains of edge-shared Cu-O6 octahedra. The chains are linked by Cu-O6 octahedra building up a wave-like layer parallel to the b/c plane. The layers are linked to each other by V—O4 tetrahedra and two sorts of trigonal bipyramids one of them containing copper. The center of the other one is statistically filled with vanadium.

Li5NaSn4 - eine Phase mit gewellten Sn-Sechsecknetzen / Li5NaSn4 - a Phase with Puckered Nets of Six-Membered Sn-Rings

1978 ◽  
Vol 33 (6) ◽  
pp. 593-596 ◽  
Author(s):  
Klaus Volk ◽  
Wiking Müller
Keyword(s):  
Crystal Structure ◽  
Diamond Lattice ◽  
The Other ◽  
Space Group ◽  
Structural Relations

Abstract The new compound LisNaSiu has been prepared and its crystal structure determined. It crystallizes trigonal, a = 471.0 ± 0.6 pm, c = 3172 ± 5 pm, space group R3m-C53V. Half of the Sn atoms build up a puckered net of connected six-membered rings, the other half is bound to the net atoms, forming a tetrahedral Sn-Sn coordination for these. The structural relations of this Sn sublattice to the diamond lattice are discussed

P(C6H5)4[VOBr4]: Synthese, IR-Spektrum und Kristallstruktur / P(C6H5)4[VOBr4]: Synthesis, IR Spectrum and Crystal Structure

1982 ◽  
Vol 37 (6) ◽  
pp. 699-701 ◽  
Author(s):  
Ulrich Müller ◽  
Abdel-Fatah Shihada ◽  
Kurt Dehnicke
Keyword(s):  
Crystal Structure ◽  
Ir Spectrum ◽  
Structure Type ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Lattice Constants ◽  
Dark Violet ◽  
Stretching Vibration

Abstract PPh4[VOBr4] was prepared by the reaction of PPh4Br with VOBr3 in CH2Br2 solu-tion. The structure of the dark violet crystals was determined with X-ray diffraction. PPh4[VOBr4] crystallizes in the space group P4/n with the lattice constants a = 1275.9 and c = 784.5 pm with two formula units per unit cell. The structure type corresponds to the frequently encountered AsPh4[RuNCl4] type. The VOBr4- ion forms a square pyramid; the V = O bond has a length of 155 pm. In the IR spectrum, the V -O stretching vibration appears at 922 cm-1 .

Monoclinic and Hexagonal Nepheline Structures of (Na3/4/K1/4)AlGeO4

1998 ◽  
Vol 54 (3) ◽  
pp. 211-220 ◽  
Author(s):  
R. P. Hammond ◽  
J. Barbier
Keyword(s):  
Large Family ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Silicate Mineral ◽  
Tetrahedral Framework ◽  
Space Group ◽  
Cell Parameters ◽  
Monoclinic Form ◽  
Hexagonal Form ◽  
Alkali Atoms

Hexagonal (Na3/4K1/4)AlGeO4 crystallizes in the space group P63 with unit-cell parameters a = 10.164 (2), c = 8.540 (2) Å and Z = 8 [wR(F 2) = 0.066 for all 3060 independent reflections]. Monoclinic (Na3/4K1/4)AlGeO4 crystallizes in the space group P21 with unit-cell parameters a = 10.0477 (4), b = 8.5764 (4), c = 10.2118 (4) Å, β = 119.035 (1)° and Z = 8 [wR(F 2) = 0.120 for all 3194 independent reflections measured on a twinned crystal]. Both structures belong to the large family of stuffed tridymites, with the Al and Ge atoms occupying tetrahedral sites, and the alkali atoms occupying the cavities of the tetrahedral framework. Hexagonal (Na3/4K1/4)AlGeO4 is isostructural with the silicate mineral nepheline (Na3/4K1/4)AlSiO4, while monoclinic (Na3/4K1/4)AlGeO4 corresponds to a minor distortion of the nepheline structure. Chemical analysis by electron microprobe and structure determination of flux-grown single crystals indicate that the hexagonal form with the chemical formula (Na0.78K0.19)Al0.97Ge1.03O4 may be stabilized by an alkali deficiency similar to that found in hexagonal natural nephelines. In contrast, all alkali sites are fully occupied in the monoclinic form of composition (Na0.75K0.25)AlGeO4 and the lower symmetry eliminates the oxygen disorder present in the hexagonal form.

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