Zwei Metasilicate mit Vierer-Einfach-Ketten: Hochdrucksynthese und Strukturverfeinerung von Sr2(VO)2Si4O12 (Haradait) und Sr2(TiO)2Si4O12 / Two Metasilicates with Vierer Single Chains: High-Pressure Synthesis and Structure Refinement of Sr2(VO)2Si4O12 (Haradaite) and Sr2(TiO )2Si4O12

1996 ◽  
Vol 51 (8) ◽  
pp. 1099-1103 ◽  
Author(s):  
Thomas Berger ◽  
Klaus-Jürgen Range
Keyword(s):  
High Pressure ◽  
Short Distance ◽  
Structure Refinement ◽  
Temperature Reaction ◽  
Vanadium Compound ◽  
Orthorhombic Space Group ◽  
Definite Evidence ◽  
High Temperature Reaction ◽  
High Pressure High Temperature ◽  
Pressure Synthesis

Single crystals of Sr2(VO)2Si4O12 could be obtained by high-pressure high-temperature reaction of a SrSiO3/SiO2/V2O5 mixture in a modified Belt-type apparatus. The green crystals are orthorhombic, space group Cmcm, with a = 5.3139(3), b = 14.6281(7), c = 7.0329(4) Å and Z = 2. The structure comprises vierer single chains of SiO4 tetrahedra, the resulting Si4O12 units being connected by VO5 square pyramids. There is one short distance (V - O = 1.61 (1) Å) within the square pyramid, giving definite evidence to a (VO)2+ group with a V = O double bond.The crystal structure of microcrystalline Sr2(TiO)2Si4O12, obtained by high-pressure hightemperature reaction of a SrSiO3/SiO2/TiO2 mixture, was refined by the Rietveld technique. The compound (Cmcm, a = 5.3530(2), b = 14.4864(7), c = 7.0817(3) Å, Z = 2) is isostructural with the vanadium compound.

Ni6B22O39·H2O – extending the field of nickel borates

2017 ◽  
Vol 72 (12) ◽  
pp. 967-975 ◽  
Author(s):  
Martin K. Schmitt ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Temperature ◽  
Temperature Reaction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
High Temperature Reaction ◽  
High Pressure High Temperature ◽  
Related Phase

AbstractNi6B22O39·H2O was synthesized in a high-pressure/high-temperature reaction at 5 GPa/900°C. It crystallizes in the orthorhombic space group Pmn21 (no. 31) with the lattice parameters a=7.664(2), b=8.121(2) and c=17.402(2) Å. The crystal structure is discussed with regard to the isotypic compounds M6B22O39·H2O (M=Fe, Co) and the structurally related phase Cd6B22O39·H2O. Furthermore, the characterization of Ni6B22O39·H2O via X-ray powder diffraction and vibrational spectroscopy is reported.

High-pressure synthesis and crystal structure of In3B5O12

2017 ◽  
Vol 72 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Daniela Vitzthum ◽  
Michael Schauperl ◽  
Klaus R. Liedl ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Pressure Synthesis ◽  
Ir And Raman

AbstractOrthorhombic In3B5O12 was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 12.2 GPa and 1500°C. Its structure is isotypic to the rare earth analogs RE3B5O12 (RE=Sc, Er–Lu). In the field of indium borate chemistry, In3B5O12 is the third known ternary indium borate besides InBO3 and InB5O9. The crystal structure of In3B5O12 has been determined via single-crystal X-ray diffraction data collected at room temperature. It crystallizes in the orthorhombic space group Pmna with the lattice parameters a=12.570(2), b=4.5141(4), c=12.397(2) Å, and V=703.4(2) Å3. IR and Raman bands of In3B5O12 were theoretically determined and assigned to experimentally recorded spectra.

Notizen: Sodium Metaperrhenate, NaReO4: High Pressure Synthesis of Single Crystals and Structure Refinement

1995 ◽  
Vol 50 (9) ◽  
pp. 1417-1418 ◽  
Author(s):  
Alexandra Atzesdorfer ◽  
Klaus-Jürgen Range
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Single Crystals ◽  
Sodium Nitrate ◽  
Structure Refinement ◽  
Type Structure ◽  
Space Group ◽  
High Pressure Synthesis ◽  
High Pressure High Temperature ◽  
Pressure Synthesis

Single crystals of sodium metaperrhenate, NaReO4, have been obtained by oxidation of rhenium metal with sodium nitrate under high pressure- high temperature conditions (modified Belttype apparatus, 4 kbar, 400 °C, Au-capsules). The crystals are tetragonal, space group I41/a, with a = 5.3654(4), c = 11.732(2) Å and Z = 4. The structure was refined to R - 0.026, Rw = 0.013 for 382 unique, absorption-corrected reflections. The scheelite-type structure for NaReO4, proposed by Beintema in 1937, could be confirmed. It consists of isolated ReO4 tetrahedra (Re-O= 1.728(2) Å ), connected by NaOs dodecahedra (<Na- O > = 2.582(2) Å).

Hochdrucksynthese und Kristallstruktur von Nd4Au2O9 und Gd4Au2O9 / High Pressure Synthesis and Crystal Structure of Nd4Au2O9 and Gd4Au2O9

1996 ◽  
Vol 51 (6) ◽  
pp. 811-816 ◽  
Author(s):  
Claudia Steiner ◽  
Martina Andratschke ◽  
Klaus-Jürgen Range
Keyword(s):  
High Pressure ◽  
Columnar Structure ◽  
Orthorhombic Space Group ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Square Planar ◽  
Pressure Synthesis ◽  
Gold Metal ◽  
Type Apparatus

Abstract Single crystals of Nd4Au2O9 and Gd4Au2O9 have been prepared by oxidizing mixtures of gold metal and Nd2O3 or Gd2O3, rsp., with KO2 under high-pressure high-temperature conditions (40 kbar, 1200°C) in a modified Belt-type apparatus. The X-ray structure analyses have been carried out on twinned crystals. The compounds crystallize in the orthorhombic space group Pbcn (Nd4Au,O9: a = 11.938(7) ,b = 6.126(2),c = 11.928(3) A ,Z = 4,1 = 0.0443; Gd4Au2O9: a = 11.922(2), 6 = 6.1242(7), c = 11.917(2) A, Z = 4. R1 =0.0232). The title compounds are isostructural with La4Au2O9. Their structure comprises isolated square-planar AuO4 groups, stacked along [010] to form a columnar structure. The Au-Au distance along the columnar direction is 3.10 Å. Structural relations to Bi2CuO4 und (Nd, Pr)2AuO5 are discussed

scholarly journals High-pressure Synthesis of New layered Oxyhalide Perovskites

2014 ◽  
Vol 70 (a1) ◽  
pp. C762-C762
Author(s):  
Yoshihiro Tsujimoto ◽  
Yoshitaka Matsushita ◽  
Kazunari Yamaura ◽  
Tetsuo Uchikoshi
Keyword(s):  
High Pressure ◽  
Magnetic Properties ◽  
High Temperature ◽  
Transition Metal Oxides ◽  
Temperature Reaction ◽  
High Temperature Reaction ◽  
Square Planar ◽  
Pressure Synthesis ◽  
Structural And Magnetic Properties ◽  
High Valent

The development of transition metal oxides with perovskite-based structure has stimulated the search for mixed anion systems such as oxynitrides, oxyhalides and oxysulfides because incorporation of two different anions in one structure offers further opportunity to effectively induce chemical and physical properties that the pure oxides cannot possess. Such mixed anion phases, however, are difficult to be synthesized by a conventional high-temperature reaction. In this study, we have employed a high pressure technique to overcome this issue, and succeessfully synthesized a series of new layered oxhalide compounds. We present structural and magnetic properties of high-valent nickel oxyhalides Sr2NiO3X (X = F, Cl), and square-planar coordinated oxychlorides Sr2MO2Cl2 (Mn, Ni) and Ba2PdO2Cl2, isostructural with superconducting parent compund Ca2CuO2Cl2.

scholarly journals High-pressure synthesis and crystal structure of the samarium meta-oxoborate γ-Sm(BO2)3

2020 ◽  
Vol 75 (6-7) ◽  
pp. 589-595
Author(s):  
Birgit Fuchs ◽  
Robert O. Kindler ◽  
Gunter Heymann ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Rare Earth ◽  
Earth Element ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Pressure Synthesis

Abstractγ-Sm(BO2)3 was obtained via a high-pressure/high-temperature approach in a multi-anvil apparatus at 10 GPa and 1673 K. It crystallizes in the orthorhombic space group Pca21 (no. 29) with the lattice parameters a = 18.3088(8), b = 4.4181(2), and c = 4.2551(2) Å. The compound was analysed by means of X-ray diffraction and vibrational spectroscopy. The structure is isotypic to that of the already known meta-oxoborates γ-RE(BO2)3 (RE = La−Nd) and built up of a highly condensed borate framework containing three-, four-, six-, and ten-membered rings. Next to neodymium, samarium represents the second rare earth element that forms the α-, β-, and γ-modification of the four known rare earth meta-oxoborate structure types.

scholarly journals High-pressure synthesis and crystal structure of the mixed-cation borate Ga4In4B15O33(OH)3

2019 ◽  
Vol 74 (4) ◽  
pp. 357-363
Author(s):  
Daniela Vitzthum ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Temperature ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Mixed Cation ◽  
High Pressure High Temperature ◽  
Pressure Synthesis

AbstractThe mixed cation triel borate Ga4In4B15O33(OH)3 was synthesized in a Walker-type multianvil apparatus at high-pressure/high-temperature conditions of 12.5 GPa and 1300°C. Although the product could not be reproduced in further experiments, its crystal structure could be reliably determined via single-crystal X-ray diffraction data. Ga4In4B15O33(OH)3 crystallizes in the tetragonal space group I41/a (origin choice 2) with the lattice parameters a = 11.382(2), c = 15.244(2) Å, and V = 1974.9(4) Å3. The structure of the quaternary triel borate consists of a complex network of BO4 tetrahedra, edge-sharing InO6 octahedra in dinuclear units, and very dense edge-sharing GaO6 octahedra in tetranuclear units.

scholarly journals High-pressure synthesis and characterization of the non-centrosymmetric scandium borate ScB6O9(OH)3

2020 ◽  
Vol 75 (6-7) ◽  
pp. 597-603
Author(s):  
Birgit Fuchs ◽  
Hubert Huppertz
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Structure Solution ◽  
Temperature Experiment ◽  
Pressure Synthesis

AbstractThe non-centrosymmetric scandium borate ScB6O9(OH)3 was obtained through a high-pressure/high-temperature experiment at 6 GPa and 1473 K. Single-crystal X-ray diffraction revealed that the structure is isotypic to InB6O9(OH)3 containing borate triple layers separated by scandium layers. The compound crystallizes in the space group Fdd2 with the lattice parameters a = 38.935(4), b = 4.4136(4), and c = 7.6342(6) Å. Powder X-ray diffraction and vibrational spectroscopy were used to further characterize the compound and verify the proposed structure solution.

Study of high-pressure air jet controlled compression ignition with compound thermodynamic cycle for combustion and emission formation process

2020 ◽  
pp. 146808742096933
Author(s):  
Xiangyu Meng ◽  
Sicheng Liu ◽  
Jingchen Cui ◽  
Jiangping Tian ◽  
Wuqiang Long ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Low Temperature ◽  
Formation Process ◽  
Combustion Process ◽  
Thermodynamic Cycle ◽  
Compression Ignition ◽  
Temperature Reaction ◽  
Air Jet ◽  
High Temperature Reaction

A novel method called high-pressure air (HPA) jet controlled compression ignition (JCCI) based on the compound thermodynamic cycle was investigated in this work. The combustion process of premixed mixture can be controlled flexibly by the high-pressure air jet compression, and it characterizes the intensified low-temperature reaction and two-stage high-temperature reaction. The three-dimensional (3D) computational fluid dynamics (CFD) numerical simulation was employed to study the emission formation process and mechanism, and the effects of high-pressure air jet temperature and duration on emissions were also investigated. The simulation results showed that the NOx formation is mainly affected by the first-stage high-temperature reaction due to the higher reaction temperature. Overall, this combustion mode can obtain ultra-low NOx emission. The second-stage high-temperature reaction plays an important role in the CO and THC formation caused by the mixing effect of the high-pressure air and original in-cylinder mixture. The increasing air jet temperature leads to a larger high-temperature in-cylinder region and more fuel in the first-stage reaction, and therefore resulting in higher NOx emission. However, the increasing air jet temperature can significantly reduce the CO and THC emissions. For the air jet duration comparisons, both too short and too long air jet durations could induce higher NOx emission. A higher air jet duration would result in higher CO emission due to the more high-pressure air jet with relatively low temperature.

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