Zur Kenntnis von SrCo2V2O8 und SrCo2(AsO4)2 / On SrCo2V2O8 and SrCo2(AsO4)2

1994 ◽  
Vol 49 (7) ◽  
pp. 923-926 ◽  
Author(s):  
D. Osterloh ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Single Crystal ◽  
Tetragonal Symmetry ◽  
Space Group ◽  
X Ray ◽  
Symmetry Space ◽  
Symmetry Space Group

SrCo2V2O8 (I) and SrCo2(As04)2 (II) were prepared by crystallization from melts and investigated by X-ray single crystal technique. (I) is isotypic to the SrNi2V2O8-type and crys­tallizes with tetragonal symmetry, space group C124v-I41cd, a = 12.267: c = 8.424 Å: Z = 8. (II) is isotypic to the lately found SrNi2(PO4)2, space group C1i-P1̅, a = 5.713; b = 6.903; c = 9.417 Å: a = 110.48; β = 101.43; γ = 99.13°, Z = 2.

Zur Kenntnis des Kupfer-Oxid-Arsenats Cu4O(A sO4)2 / On the Copper Oxide Arsenate Cu4O(AsO4)2

1996 ◽  
Vol 51 (9) ◽  
pp. 1279-1282 ◽  
Author(s):  
M. Staack ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
Copper Oxide ◽  
Single Crystal ◽  
Copper Ions ◽  
Space Group ◽  
X Ray ◽  
Different Types ◽  
Symmetry Space ◽  
Symmetry Space Group ◽  
Anionic Part

The copper oxide arsenate Cu4O(AsO4)2 has been prepared and investigated by single crystal X-ray techniques. The compound crystallizes with triclinic symmetry, space group C1i-P1̄, a = 6.4148(7), b = 7.6549(5), c = 8.2241(7) Å, α = 98.52(1), β = 112.39(1), 7 = 98.38(1)°, Z = 2. Cu4O(AsO4)2 is isotypic to Cu4(PO4)2O . Copper ions on one of the four specified sites show nearly planar coordination by O2- and may be assigned to the anionic part of the crystal structure. One of the nine different types of oxygen atoms is coordinated by copper exclusively. The compound is therefore classified as an oxide arsenate.

scholarly journals Synthese und Kristallstruktur eines Alkali-Erdalkali-Kupfer-Halogeno-Oxovanadats: KBaCuV2O7Cl / Synthesis and Crystal Structure of an Alkaline Alkaline-Earth Halide Oxide of Copper and Vanadium: KBaCuV2O7Cl

1994 ◽  
Vol 49 (3) ◽  
pp. 355-359 ◽  
Author(s):  
F.-D. Martin ◽  
H. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Alkaline Earth ◽  
Copper Ion ◽  
Tetragonal Symmetry ◽  
Synthesis And Crystal Structure ◽  
Space Group ◽  
X Ray ◽  
Symmetry Space ◽  
Symmetry Space Group

Abstract Single crystals of KBaCuV2O7Cl have been prepared by a flux technique and investigated by X-ray analysis. The compound crystallizes with tetragonal symmetry, space group C24v-P4 bm, a = 8.8581, c = 5.4711 Å, Z = 2. The crystal structure shows Cu2+ within a one sided strongly distorted CuO4Cl2 octahedron. The copper ion is shifted towards the nearer Cl- neighbour to form a CuO4Cl square pyramid. Two VO4 tetrahedra are connected to give stretched V2O7 double tetrahedra, and linked in planes via the oxygen corners of the CuO4Cl pyramids. The crystal structure and the structure of the complex BaO8Cl2 polyhedron are discussed.

Synthese und Röntgen-Strukturuntersuchung von Rb4Cd(VO)(V2O7)2Cl und Tl4Cd(VO)(V2O7)2Cl / Synthesis and X-Ray Structure Analysis of Rb4Cd(VO)(V2O7)2Cl und Tl4Cd(VO)(V2O7)2Cl

1997 ◽  
Vol 52 (4) ◽  
pp. 453-456 ◽  
Author(s):  
B. Mertens ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Single Crystals ◽  
Structure Analysis ◽  
Tetragonal Symmetry ◽  
Space Group ◽  
X Ray ◽  
Vanadyl Group ◽  
Type V ◽  
Symmetry Space ◽  
Symmetry Space Group

Abstract Single crystals of (I) Rb4Cd(VO)(V2O7)2Cl und Tl4Cd(VO)(V2O7)2Cl have been prepared by flux techniques. The compounds were examined by X-ray analysis. They crystallize with tetragonal symmetry, space group C14-P4 with (I): a=9.142(1); c=5.525(1), (II): a=9.150(1), c=5.405(1) A, Z = 4. Both compound belong to the K4CuV5O15Cl-Type. V (l) forms V2O7 double tetrahedra, connected by square V(2)O5 pyramids and CdO4Cl2 octahedra. The short V(2)-O distance indicates a vanadyl group.

Darstellung und Strukturbeschreibung von NaCa3 Mn(V2O7)(V3O10) / Preparation and Structure of NaCa3Mn(V2O7)(V3O10)

1998 ◽  
Vol 53 (5-6) ◽  
pp. 507-511 ◽  
Author(s):  
R. Rettich ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Argon Atmosphere ◽  
Statistical Distribution ◽  
The Other ◽  
Space Group ◽  
X Ray ◽  
Point Position ◽  
Symmetry Space ◽  
Symmetry Space Group

Abstract Single crystals of NaCa3 Mn(V2O7)(V3O10) have been prepared by crystallization from flux in argon atmosphere. X-Ray single crystal methods led to triclinic symmetry, space group C1i - P 1̄, a = 6.8798(9), b = 6.902(1), c = 15.480(2) Å, α = 87.39(1), β = 85.32(1), γ = 86.25(2) °, Z = 2. The compound belongs to the rare trivanadates showing V2O7 and V3O10 groups incorporated into a NaCaMn/O framework. One point position of the cations is occupied by Ca2+, three by Na+ and Ca2+ in a statistical distribution and a fourth one by Mn2+. The surrounding of Mn2+ and the statistically occupied position M(3) are octahedra, the other metal positions are centers of capped trigonal prisms.

Geschlossene 1∞[(PtDy4O16)4]-Polyedertunnel in Ba13Dy8Zn4Pt4O37 Closed 1∞ [(PtDy4O16)4] Polyhedra Tunnels in Ba13Dy8Zn4Pt4O37

1997 ◽  
Vol 52 (5) ◽  
pp. 553-556 ◽  
Author(s):  
O. Sfreddo ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Tetragonal Symmetry ◽  
Space Group ◽  
X Ray ◽  
Coordination Numbers ◽  
Symmetry Space ◽  
Symmetry Space Group ◽  
Trigonal Prisms

Abstract Single crystals of Ba13Dy8Zn4Pt4O37 have been prepared by reaction of mixtures of BaCO3, ZnO and DyO3 at temperatures up to 1225 °C using platinum crucibles. X-ray investigations led to a new crystal structure with tetragonal symmetry, space group C4h5-I4/m, a = 18.659(7), c = 5.734(2) Å, Z = 2. The structure is characterized by PtO6 and BaO6 octahedra as well as by tetragonal ZnO5 pyramids and single capped trigonal prisms of oxygen around dysprosium. The remaining barium positions show coordination numbers of nine and ten. The crystal structure has large ∞1[(PtDy4O)6)4] polyhedra tunnels. Considering the ∞1[Ln4O16]20- polyhedra groups some parts of the structure show similarities to BaZnLn2O5, Ba5Zn4Ln8O21 and Ba2Ln2ZnPtO8.

scholarly journals Twinning, Superstructure and Chemical Ordering in Spryite, Ag8(As3+0.50As5+0.50)S6, at Ultra-Low Temperature: An X-Ray Single-Crystal Study

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 286
Author(s):  
Luca Bindi ◽  
Marta Morana
Keyword(s):  
Single Crystal ◽  
Point Of View ◽  
New Mineral ◽  
Orthorhombic Symmetry ◽  
Temperature Structure ◽  
Crystal Chemical ◽  
Space Group ◽  
X Ray ◽  
Symmetry Space ◽  
Symmetry Space Group

Spryite (Ag7.98Cu0.05)Σ=8.03(As5+0.31Ge0.36As3+0.31Fe3+0.02)Σ=1.00S5.97, and ideally Ag8(As3+0.5As5+0.5)S6, is a new mineral recently described from the Uchucchacua polymetallic deposit, Oyon district, Catajambo, Lima Department, Peru. Its room temperature structure exhibits an orthorhombic symmetry, space group Pna21, with lattice parameters a = 14.984(4), b = 7.474(1), c = 10.571(2) Å, V = 1083.9(4) Å3, Z = 4, and shows the coexistence of As3+ and As5+ distributed in a disordered fashion in a unique mixed position. To analyze the crystal-chemical behaviour of the arsenic distribution at ultra-low temperatures, a structural study was carried out at 30 K by means of in situ single-crystal X-ray diffraction data (helium-cryostat) on the same sample previously characterized from a chemical and structural point of view. At 30 K, spryite still crystallizes with orthorhombic symmetry, space group Pna21, but gives rise to a a × 3b × c superstructure, with a = 14.866(2), b = 22.240(4), c = 10.394(1) Å, V = 3436.5(8) Å3 and Z = 4 (Ag24As3+As5+Ge4+S18 stoichiometry). The twin laws making the twin lattice simulating a perfect hexagonal symmetry have been taken into account and the crystal structure has been solved and refined. The refinement of the structure leads to a residual factor R = 0.0329 for 4070 independent observed reflections [with Fo > 4σ(Fo)] and 408 variables. The threefold superstructure arises from the ordering of As3+ and (As5+, Ge4+) in different crystal-chemical environments.

Weitere Verbindungen des Ba17Ln16Zn8Pt4O57- Typs mit Ln = Dy, Ho, Er, Y / More Compounds of the Ba17Ln16Zn8Pt4O57 Type with Ln = Dy, Ho, Er, Y

1997 ◽  
Vol 52 (9) ◽  
pp. 1067-1071 ◽  
Author(s):  
O. Sfreddo ◽  
Hk. Müller-Buschbaum
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Single Crystals ◽  
Tetragonal Symmetry ◽  
Space Group ◽  
X Ray ◽  
High Temperature Reactions ◽  
Symmetry Space ◽  
Symmetry Space Group

Abstract Single crystals of Ba17Dy16Zn8Pt4O57 (I), Ba17Ho16Zn8Pt4O57 (II), Ba17Er16Zn8Pt4O57 (III) and Ba17YZn8Pt4O57 (IV) have been prepared by high temperature reactions using platinum crucibles. X-ray investigations led to tetragonal symmetry, space group C54h - I4/m, (I) - (IV): a = 22.905(1), 22.840(1), 22.795(1), 22.848(1) Å and c = 5.728(1), 5.722(1), 5.700(1), 5.709(1) Å,Z = 2. The crystal structure is characterized by small square, medium-sized quadrangular and large rectangular tunnels, which are filled by oxygen, barium and zinc. The polyhedra network is discussed with respect to the network of compounds of the Ba13Dy8Zn4Pt4O37 type.

scholarly journals Photoconductivity of the Single Crystals Pb4Ga4GeS12 and Pb4Ga4GeSe12

Proceedings ◽  
2020 ◽  
Vol 62 (1) ◽  
pp. 4
Author(s):  
Hadj Bellagra ◽  
Oksana Nyhmatullina ◽  
Yuri Kogut ◽  
Halyna Myronchuk ◽  
Lyudmyla Piskach
Keyword(s):  
Ternary Systems ◽  
Semiconductor Materials ◽  
Tetragonal Symmetry ◽  
Bandgap Energy ◽  
Experimental Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vertical Bridgman ◽  
Symmetry Space ◽  
Symmetry Space Group

Quaternary semiconductor materials of the Pb4Ga4GeS(Se)12 composition have attracted the attention of researchers due to their possible use as active elements of optoelectronics and nonlinear optics. The Pb4Ga4GeS(Se)12 phases belong to the solid solution ranges of the Pb3Ga2GeS(Se)8 compounds which form in the quasi-ternary systems PbS(Se)−Ga2S(Se)3−GeS(Se)2 at the cross of the PbGa2S(Se)4−Pb2GeS(Se)4 and PbS(Se)−PbGa2GeS(Se)6 sections. The quaternary sulfide melts congruently at 943 K. The crystallization of the Pb4Ga4GeSe12 phase is associated with the ternary peritectic process Lp + PbSe ↔ PbGa2S4 + Pb3Ga2GeSe8 at 868 K. For the single crystal studies, Pb4Ga4GeS(Se)12 were pre-synthesized by co-melting high-purity elements. The X-ray diffraction results confirm that these compounds possess non-centrosymmetric crystal structure (tetragonal symmetry, space group P–421c). The crystals were grown by the vertical Bridgman method in a two-zone furnace. The starting composition was stoichiometric for Pb4Ga4GeS12, and the solution-melt method was used for the selenide Pb4Ga4GeSe12. The obtained value of the bandgap energy for the Pb4Ga4GeS12 and Pb4Ga4GeSe12 crystals is 1.86 and 2.28 eV, respectively. Experimental measurements of the spectral distribution of photoconductivity for the Pb4Ga4GeS12 and Pb4Ga4GeSe12 crystals exhibit the presence of two spectral maxima. The first lies in the region of 570 (2.17 eV) and 680 nm (1.82 eV), respectively, and matches the optical bandgap estimates well. The locations of the admixture maxima at about 1030 (1.20 eV) and 1340 nm (0.92 eV), respectively, agree satisfactorily with the calculated energy positions of the defects vs. and VSe.

scholarly journals Low-Temperature Ordering in the Cluster Compound (Bi8)Tl[AlCl4]3

Inorganics ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 45 ◽  
Author(s):  
Maximilian Knies ◽  
Martin Kaiser ◽  
Mai Lê Anh ◽  
Anastasia Efimova ◽  
Thomas Doert ◽  
...  
Keyword(s):  
Cluster Compound ◽  
Structure Model ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
Threefold Axis ◽  
Space Group ◽  
X Ray ◽  
A Chain ◽  
Symmetry Space ◽  
Symmetry Space Group

The reaction of Bi, BiCl3, and TlCl in the ionic liquid [BMIm]Cl·4AlCl3 (BMIm = 1-n-butyl-3-methylimidazolium) at 180 °C yielded air-sensitive black crystals of (Bi8)Tl[AlCl4]3. X-ray diffraction on single crystals at room temperature revealed a structure containing [ Tl ( AlCl 4 ) 3 ] ∞ 1 2 − strands separated by isolated Bi82+ square antiprisms. The thallium(I) ion is coordinated by twelve Cl− ions of six [AlCl4]− groups, resulting in a chain of face-sharing [TlCl12]11− icosahedra. The Bi82+ polycation is disordered, simulating a threefold axis through its center and overall hexagonal symmetry (space group P63/m). Slowly cooling the crystals to 170 K resulted in increased order in the Bi8 cluster orientations. An ordered structure model in a supercell with a’ = 2a, b’ = 2b, c’ = 3c and the space group P65 was refined. The structure resembles a hexagonal perovskite, with complex groups in place of simple ions.

A New Copper (II) Complex with the N,N'-Bis(antipyryl-4-methyl)-piperazine (BAMP) Ligand: [Cu(BAMP)](ClO4)2

2002 ◽  
Vol 57 (12) ◽  
pp. 1454-1460 ◽  
Author(s):  
Otilia Costișor ◽  
Ramona Tudose ◽  
Ingo Pantenburg ◽  
Gerd Meyer
Keyword(s):  
Crystal Structure ◽  
Copper Complex ◽  
Structural Parameters ◽  
Complex Molecule ◽  
Lattice Parameters ◽  
Tetragonal Symmetry ◽  
Apical Position ◽  
Space Group ◽  
Symmetry Space ◽  
Symmetry Space Group

The synthesis of the Mannich base N,N’-bis(antipyryl-4-methyl)-piperazine (BAMP) (1), its crystal structure as well as the synthesis and the crystal structure of the copper complex Cu(BAMP)(ClO4)2 (2) are reported. C28H34N6O2 ∙ 4H2O (BAMP ∙ 4H2O) crystallizes with triclinic symmetry, space group P1̄, lattice parameters: a = 704,9(2), b = 983,4(2), c = 1198,9(3) pm, α = 68,72°, β = 73,62°, γ = 78,49°. The copper-complex Cu(BAMP)(ClO4)2 crystallizes with tetragonal symmetry, space group P42/n, lattice parameters: a = 2295,1(3), c = 1412,2(2) pm. The copper(II) atom is five-coordinate by the two nitrogen atoms belonging to the piperazine ring and the oxygen atoms of the antipyrinemoieties. The geometry of the copper(II) atom can be described as a square-based pyramid with the N2O2 donor atoms of BAMP forming the basal plane and an oxygen atom of the neighbouring complex molecule occupying the apical position. BAMP acts as a tetradentate ligand, which incorporates a piperazine-fused ring. The structural parameters illustrate well the reinforcing effect exerted by the double “straps” of the piperazine molecule.

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