Die Kristallstrukturen von PPh4[SnCl3] und PPh4[SnBr3]/ The Crystal Structures of PPh4[SnCl3] and PPh4[SnBr3]

1982 ◽  
Vol 37 (9) ◽  
pp. 1122-1126 ◽  
Author(s):  
Ulrich Müller ◽  
Norbert Mronga ◽  
Christina Schumacher ◽  
Kurt Dehnicke

AbstractPPh4[SnCl3] and PPh4[SnBr3] were prepared by reaction of PPh4X with SnX2 in CH2X2 solutions (X - Cl, Br). The vibrational spectra of the [SnX3]⊖ ions show three SnX3 stretching frequencies, which is caused by deviations from the ideal C3v symmetry. In the crystal structure determinations these deviations show up by slightly different Sn-X bond lengths which are explained by differing hydrogen bridges to phenyl-H atoms. The isotypic crystal structures of both compounds were determined and refined from X-ray diffraction data (R values: 0.042 and 0.034). Although triclinic (space group P1̄), the structures are closely related to the tetragonal AsPh4[RuNCl4] structure type. Very pure SnBr2 is prepared by the reaction of PPh4[SnBr3] with AlBr3 in CH2Br2 solution.

2004 ◽  
Vol 19 (3) ◽  
pp. 280-283 ◽  
Author(s):  
D. D. Khalyavin ◽  
A. M. R Senos ◽  
P. Q. Mantas

The crystal structures of Sr2MgWO6 and Ba2SrWO6 compounds, studied by powder X-ray diffraction, were found to be distorted perovskites with a complete NaCl type ordering between Mg2+/W6+ and Sr2+/W6+ ions, respectively. The unit cells are characterized by the tetragonal (space group I4/m; a0a0a−) symmetry, with the parameters a=5.5849(10) Å and c=7.9455(10) Å, for Sr2MgWO6 and triclinic (space group F-1; a−b−b−) symmetry, with the parameters a=8.5409(10) Å, b=c=8.5860(10) Å, α=89.35(1)° and β=γ=90.31(1)°, for Ba2SrWO6. © 2004 International Centre for Diffraction Data.


2013 ◽  
Vol 28 (1) ◽  
pp. 13-17 ◽  
Author(s):  
F. Laufek ◽  
A. Vymazalová ◽  
D.A. Chareev ◽  
A.V. Kristavchuk ◽  
J. Drahokoupil ◽  
...  

The (Ag,Pd)22Se6 phase was synthesized from individual elements by silica glass tube technique and structurally characterized from powder X-ray diffraction data. The (Ag,Pd)22Se6 phase crystallizes in Fm$\overline3$m symmetry, unit-cell parameters: a = 12.3169(2) Å, V = 1862.55(5) Å3, Z = 4, and Dc = 10.01 g/cm3. The crystal structure of the (Ag,Pd)22Se6 phase represents a stuffed 3a.3a.3a superstructure of the Pd structure (fcc), where only 4 from 108 available octahedral holes are occupied. Its crystal structure is related to the Cr23C6 structure type.


Author(s):  
Gohil S. Thakur ◽  
Hans Reuter ◽  
Claudia Felser ◽  
Martin Jansen

The crystal structure redetermination of Sr2PdO3 (distrontium palladium trioxide) was carried out using high-quality single-crystal X-ray data. The Sr2PdO3 structure has been described previously in at least three reports [Wasel-Nielen & Hoppe (1970). Z. Anorg. Allg. Chem. 375, 209–213; Muller & Roy (1971). Adv. Chem. Ser. 98, 28–38; Nagata et al. (2002). J. Alloys Compd. 346, 50–56], all based on powder X-ray diffraction data. The current structure refinement of Sr2PdO3, as compared to previous powder data refinements, leads to more precise cell parameters and fractional coordinates, together with anisotropic displacement parameters for all sites. The compound is confirmed to have the orthorhombic Sr2CuO3 structure type (space group Immm) as reported previously. The structure consists of infinite chains of corner-sharing PdO4 plaquettes interspersed by SrII atoms. A brief comparison of Sr2PdO3 with the related K2NiF4 structure type is given.


Author(s):  
Takashi Mochiku ◽  
Yoshitaka Matsushita ◽  
Nikola Subotić ◽  
Takanari Kashiwagi ◽  
Kazuo Kadowaki

RhPb2 (rhodium dilead) is a superconductor crystallizing in the CuAl2 structure type (space group I4/mcm). The Rh and Pb atoms are located at the 4a (site symmetry 422) and 8h (m.2m) sites, respectively. The crystal structure is composed of [RhPb8] antiprisms, which share their square faces along the c axis and the edges in the direction perpendicular to the c axis. We have succeeded in growing single crystals of RhPb2 and have re-determined the crystal structure on basis of single-crystal X-ray diffraction data. In comparison with the previous structure studies using powder X-ray diffraction data [Wallbaum (1943). Z. Metallkd. 35, 218–221; Havinga et al. (1972). J. Less-Common Met. 27, 169–186], the current structure analysis of RhPb2 leads to more precise unit-cell parameters and fractional coordinates, together with anisotropic displacement parameters for the two atoms. In addition and likewise different from the previous studies, we have found a slight deficiency of Rh in RhPb2, leading to a refined formula of Rh0.950 (9)Pb2.


IUCrData ◽  
2019 ◽  
Vol 4 (11) ◽  
Author(s):  
Artem V. Malin ◽  
Sergei I. Ivlev ◽  
Roman V. Ostvald ◽  
Florian Kraus

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].


Author(s):  
P. Bayliss ◽  
N. C. Stephenson

SummaryThe crystal structure of gersdorffite (III) has been examined with three-dimensional Weissenberg X-ray diffraction data. The unit cell is isometric with a 5·6849 ± 0·0003 Å, space group PI, and four formula units per cell. This structure has the sulphur and arsenic atoms equally distributed over the non-metal atom sites of pyrite. All atoms show significant random displacements from the ideal pyrite positions to produce triclinic symmetry, which serves to distinguish this mineral from a disordered cubic gersdorffite (II) and a partially ordered cubic gersdorffite (I). Factors responsible for the atomic distortions are discussed.


2017 ◽  
Vol 81 (2) ◽  
pp. 369-381 ◽  
Author(s):  
F. Cámara ◽  
E. Sokolova ◽  
Y. A. Abdu ◽  
F. C. Hawthorne ◽  
T. Charrier ◽  
...  

AbstractFogoite-(Y), Na3Ca2Y2Ti(Si2O7)2OF3, is a new mineral from the Lagoa do Fogo, São Miguel Island, the Azores. It occurs in cavities as highly elongated (on [001]) prisms, up to 2000 μm long and 50 μm× 50 μm in cross-section, associated with sanidine, astrophyllite, fluornatropyrochlore, ferrokentbrooksite, quartz and ferro-katophorite. Crystals are generally transparent and colourless, with vitreous lustre, occasionally creamy white. Fogoite-(Y) has a white streak, splintery fracture and very good {100} cleavage. Mohs hardness is ∼5. Dcalc. = 3.523 g/cm3. It is biaxial (+) with refractive indices (λ = 590 nm) α = 1.686(2), β = 1.690(2), γ = 1.702(5); 2Vmeas. = 57(1)° and 2Vcalc. = 60°. It is nonpleochroic. Fogoite-(Y) is triclinic, space group P1, a = 9.575(6), b = 5.685(4), c = 7.279(5) Å, α = 89.985(6), β = 100.933(4), γ = 101.300(5)°, V = 381.2 (7) Å3. The six strongest reflections in the powder X-ray diffraction data [d (Å), I, (hkl)] are: 2.954, 100, (1̄1̄2, 3̄10); 3.069, 42, (300, 01̄2); 2.486, 24, (310, 21̄2); 3.960, 23, (1̄1̄1, 2̄10); 2.626, 21, (2̄20); 1.820, 20, (1̄04). Electron microprobe analysis gave the following empirical formula calculated on 18 (O + F) (Na2.74Mn0.15)∑2.89Ca2[Y1.21(La0.01Ce0.03Nd0.03Sm0.02Gd0.08Dy0.08Er0.05Yb0.04Lu0.01)∑0.35Mn0.16Zr0.11Na0.09Fe0.072+Ca0.01]∑2(Ti0.76Nb0.23Ta0.01)∑1(Si4.03O14)O1.12F2.88, Z = 1. The crystal structure was refined on a twinnedcrystal to R1 = 2.81% on the basis of 2157 unique reflections (Fo > 4σFo) and is a framework of TS (Titanium Silicate) blocks, which consist of HOH sheets (H – heteropolyhedral, O – octahedral) parallel to (100). In the O sheet, the the [6]MO(1) site is occupied mainly by Ti, <MO(1)–ϕ> = 1.980 Å, and the [6]MO(2) and [6]MO(3) sites are occupied by Na and Na plus minor Mn, <MO(2)–ϕ>= 2.490 Å and <MO(3)–ϕ> = 2.378 Å. In the H sheet, the two [4]Si sites are occupied by Si, with <Si–O> = 1.623 Å; the [6]MH site is occupied by Y and rare-earth elements (Y > REE), with minor Mn, Zr, Na, Fe2+ and Ca, <MH–ϕ> = 2.271 Å and the [6]AP site is occupied by Ca, <AP–ϕ> = 2.416 Å. The MH and AP octahedra and Si2O7 groups constitute the H sheet. The ideal compositions of the O and two H sheets are Na3Ti(OF)F2 and Y2Ca2(Si2O7)2 apfu. Fogoite-(Y) is isostructural with götzenite and hainite. The mineral is named after the type locality, the Fogo volcano in the Azores.


1987 ◽  
Vol 42 (12) ◽  
pp. 1493-1499 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Detlev Haase

AbstractThe compounds (Pn4P)4Sb8I28 (1) and (Ph4P)Sb3I10 (2) were prepared by the reaction of SbI3 and Ph4PI in acetonitrile (molar ratios 2:1 and 3:1 respectively). The structures of 1 and 2 were determined from single crystal X-ray diffraction data.1 crystallizes in the triclinic space group P1̄ with a - 1321.7(5). b = 1346.7(5), c = 2201.8(8) pm, α = 104.18(2). β = 99.92(2), γ = 100.33(2)°; 2: monoclinic, C2/c, a = 2371.1(2), b = 745.0(1), c = 2495.1(2) pm, β = 100.75(1)°.Whereas 1 exhibits isolated Sb8I284- ions, the anions of 2 are built up of polymeric chains [Sb3I10- ]∞. In both compounds the distorted Sbl6 octahedra are linked by common edges. The Sb-I distances are in the range between 277.4 and 354.8 pm (1) and between 277.4 and 342.4 pm (2). The observed structures do not only depend on stoichiometry, the nature of the counter cations, and the possibility of oligomerisation but also on the wide variety of the Sb-I bond strengths and the different bridges formed by iodine.The lone pair of Sb(III) seems to be predominantly 5 s2.


2020 ◽  
Vol 151 (9) ◽  
pp. 1317-1328
Author(s):  
Matthias Weil ◽  
Berthold Stöger

Abstract The caesium phosphates Cs3(H1.5PO4)2(H2O)2 and Cs3(H1.5PO4)2 were obtained from aqueous solutions, and Cs4P2O7(H2O)4 and CsPO3 from solid state reactions, respectively. Cs3(H1.5PO4)2, Cs4P2O7(H2O)4, and CsPO3 were fully structurally characterized for the first time on basis of single-crystal X-ray diffraction data recorded at − 173 °C. Monoclinic Cs3(H1.5PO4)2 (Z = 2, C2/m) represents a new structure type and comprises hydrogen phosphate groups involved in the formation of a strong non-symmetrical hydrogen bond (accompanied by a disordered H atom over a twofold rotation axis) and a very strong symmetric hydrogen bond (with the H atom situated on an inversion centre) with symmetry-related neighbouring anions. Triclinic Cs4P2O7(H2O)4 (Z = 2, P$$\bar{1}$$ 1 ¯ ) crystallizes also in a new structure type and is represented by a diphosphate group with a P–O–P bridging angle of 128.5°. Although H atoms of the water molecules were not modelled, O···O distances point to hydrogen bonds of medium strengths in the crystal structure. CsPO3 is monoclinic (Z = 4, P21/n) and belongs to the family of catena-polyphosphates (MPO3)n with a repetition period of 2. It is isotypic with the room-temperature modification of RbPO3. The crystal structure of Cs3(H1.5PO4)2(H2O)2 was re-evaluated on the basis of single-crystal X-ray diffraction data at − 173 °C, revealing that two adjacent hydrogen phosphate anions are connected by a very strong and non-symmetrical hydrogen bond, in contrast to the previously described symmetrical bonding situation derived from room temperature X-ray diffraction data. In the four title crystal structures, coordination numbers of the caesium cations range from 7 to 12. Graphic abstract


1990 ◽  
Vol 43 (10) ◽  
pp. 1697 ◽  
Author(s):  
GA Bowmaker ◽  
PC Healy ◽  
LM Engelhardt ◽  
JD Kildea ◽  
BW Skelton ◽  
...  

The crystal structures of [Cu(Pme3)4]X (X = Cl , Br, I) and of [M(PPh3)4] [PF6] (M = Cu, Ag) have been determined by single-crystal X-ray diffraction methods at 295 K. The former compounds contain nearly tetrahedral [Cu(PMe3)4]+ ions on sites of m symmetry with mean Cu-P bond lengths of 2.270, 2.271 and 2.278 Ǻ for X = Cl , Br and I respectively. The latter compounds contain [M(PPh3)4]+ ions on sites of 3 symmetry. In the M =Ag complex the coordination environment is close to tetrahedral, but in the M =Cu complex the length of the axial Cu-P bond [2.465(2)Ǻ] is significantly shorter than that of the off-axis bonds [2.566(2)Ǻ]. Possible reasons for this are discussed.


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