scholarly journals Analysis of crystal structure and phase relationship of Ba2-xLaxIn2O5+δ by high temperature synchrotron X-ray diffraction and thermal analyses - Control of electrical conductivity and crystal structure by concentration of oxide ion vacancy

2009 ◽  
Vol 117 (1361) ◽  
pp. 60-65 ◽  
Author(s):  
Takuya HASHIMOTO ◽  
Takayuki SUGIMOTO ◽  
Kazuki OMOTO ◽  
Masashi YOSHINAGA ◽  
Masahiko TANAKA ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electrical Conductivity ◽  
High Temperature ◽  
Thermal Analyses ◽  
Phase Relationship ◽  
X Ray Diffraction ◽  
X Ray ◽  
Relationship Of ◽  
Oxide Ion

IV. Order–disorder transitions: solid state kinetics, thermal analyses, X-ray diffraction and electrical conductivity studies in the Ag2SO4–K2SO4 system

1985 ◽  
Vol 63 (2) ◽  
pp. 324-328 ◽  
Author(s):  
M. Sunitha Kumari ◽  
Etalo A. Secco
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Reaction Kinetics ◽  
Solid Phase ◽  
Thermal Analyses ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Liquid

Order–disorder transitions occurring in the Ag2SO4–K2SO4 system were investigated by reaction kinetics, thermal analyses, X-ray diffraction, and electrical conductivity techniques. Solid–liquid and solid–solid phase diagrams are reported.The conductivity data in the high temperature phase of the solid resemble superionic conductivity behavior. The higher conductivity of Ag2SO4 with K+ presence relative to pure Ag2SO4 and Ag2−xNaxSO4 compositions support a lattice expansion facilitating higher mobility of ions.The reaction kinetics, X-ray diffraction, and electroconductivity results suggest a relatively open periodic [Formula: see text] sublattice in the high-temperature phase of the sulfate-based systems studied in this series.

β-Ca11B2Si4O22: six-fold twinning, crystal structure and thermal expansion

2018 ◽  
Vol 233 (6) ◽  
pp. 379-390 ◽  
Author(s):  
Sergey N. Volkov ◽  
Valentina A. Yukhno ◽  
Rimma S. Bubnova ◽  
Vladimir V. Shilovskikh
Keyword(s):  
Crystal Structure ◽  
Thermal Expansion ◽  
High Temperature ◽  
Electron Backscatter Diffraction ◽  
Monoclinic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Backscatter ◽  
Backscatter Diffraction ◽  
Relationship Of

Abstract The low-temperature polymorph β-Ca11B2Si4O22 crystallizes as a monoclinic structure [space group is P21/c, a=14.059(9), b=6.834(5), c=10.597(7) Å, β=100.735(8)°]. The crystal investigated by single-crystal X-ray diffraction was a twin composed of six individuals. The crystal structure is similar to that of mineral spurrite, Ca5(SiO4)2CO3, and can be described as a framework of [CaO5] and [CaO6] polyhedra, the cavities of which are filled with [SiO4] and [BO3] groups. The orientation relationship of twin domains was investigated by electron backscatter diffraction (EBSD). Thermal expansion was studied by high-temperature X-ray powder diffraction. It is slightly anisotropic: α11=10, α22=16, α33=12×10−6°C−1 at 200°C.

Zur Polymorphie des Ba(BrO3)2 und Sr(IO3)2, Kristallstruktur, röntgenographische, schwingungsspektroskopische und thermoanalytische Untersuchungen / Polymorphism of Ba(BrO3)2 and Sr(IO3)2 — Crystal Structure, X-Ray, IR, Raman, and Thermoanalytical Data

1990 ◽  
Vol 45 (5) ◽  
pp. 587-592 ◽  
Author(s):  
Heinz Dieter Lutz ◽  
Ekrem Alici ◽  
Thomas Kellersohn ◽  
Peter Kuske
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Thermal Analyses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Raman Spectroscopic ◽  
Thermoanalytical Data ◽  
R Value ◽  
Ir And Raman ◽  
High Temperature Polymorph

The polymorphic behaviour of Ba(BrO3)2 and Sr(IO3)2 is studied by means of differential thermal analyses and high-temperature X-ray and Raman spectroscopic measurements. On dehydration of the respective monohydrates [Ba(ClO3)2 · H2O type] at low temperatures in a vacuum Ba(BrO3)2 I and α-Sr(IO3)2 (both α-Ba(IO3)2 type, space group C2/c, Z = 4) are formed. On heating these polymorphs above 145 and 240 °C, respectively, phase transitions to Ba(BrO3)2 II [Sr(ClO3)2 type] and the hitherto unknown γ-Sr(IO3)2 occur. On further heating Ba(BrO3)2 II decomposes [partly via the high-temperature polymorph Ba(BrO3)2 III] to BaBr2 and O2, γ-Sr(IO3)2 via the probably only stable polymorph β-Sr(IO3)2 to iodine and strontium paraperiodate. The IR and Raman spectra of Ba(BrO3)2 I and III, α-, β- and γ-Sr(IO3)2, and α-Ba(IO3)2 are given. The crystal structure of Ba(BrO3)2 I has been determined by single crystal X-ray diffraction. The final R value for 1586 reflections with I ≥ 2σI is 0.064. The crystal structures of the a-Ba(IO3)2 type anhydrous halates are very similar to those of the Ba(ClO3)2 · H2O type halate monohydrates.

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.

Lateral deformations of a crystal of potassium acid phthalate in an external electric field

2021 ◽  
Vol 54 (5) ◽  
pp. 1317-1326
Author(s):  
Arsen Petrenko ◽  
Nataliya Novikova ◽  
Alexander Blagov ◽  
Anton Kulikov ◽  
Yury Pisarevskii ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Electrical Conductivity ◽  
Electric Field ◽  
External Electric Field ◽  
Applied Field ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Potassium Acid Phthalate ◽  
Acid Phthalate

The anisotropy of deformations in potassium acid phthalate crystals arising under the action of an external electric field up to 1 kV mm−1 applied along the [001] polar axis was studied using X-ray diffraction methods at room temperature. Electrical conductivity was measured and rocking curves for reflections 400, 070 and 004 were obtained by time-resolved X-ray diffractometry in Laue and Bragg geometries. Two saturation processes were observed from the time dependences of the electrical conductivity. A shift in the diffraction peaks and a change in their intensity were found, which indicated a deformation of the crystal structure. Rapid piezoelectric deformation and reversible relaxation-like deformation, kinetically similar to the electrical conductivity of a crystal, were revealed. The deformation depended on the polarity and strength of the applied field. The deformation was more noticeable in the [100] direction and was practically absent in the [001] direction of the applied field. X-ray diffraction analysis revealed a disordered arrangement of potassium atoms, i.e. additional positions and vacancies. The heights of potential barriers between the positions of K+ ions and the paths of their possible migration in the crystal structure of potassium acid phthalate were determined. The data obtained by time-resolved X-ray diffractometry and X-ray structure analysis, along with additional electrophysical measurements, allow the conclusion that the migration of charge carriers (potassium cations) leads to lateral deformation of the crystal structure of potassium phthalate in an external electric field.

scholarly journals Crystal Chemistry and High-Temperature Behaviour of Ammonium Phases NH4MgCl3·6H2O and (NH4)2Fe3+Cl5·H2O from the Burned Dumps of the Chelyabinsk Coal Basin

Minerals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 486 ◽  
Author(s):  
Andrey A. Zolotarev ◽  
Elena S. Zhitova ◽  
Maria G. Krzhizhanovskaya ◽  
Mikhail A. Rassomakhin ◽  
Vladimir V. Shilovskikh ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Coal Basin ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Mineral Phases

The technogenic mineral phases NH4MgCl3·6H2O and (NH4)2Fe3+Cl5·H2O from the burned dumps of the Chelyabinsk coal basin have been investigated by single-crystal X-ray diffraction, scanning electron microscopy and high-temperature powder X-ray diffraction. The NH4MgCl3·6H2O phase is monoclinic, space group C2/c, unit cell parameters a = 9.3091(9), b = 9.5353(7), c = 13.2941(12) Å, β = 90.089(8)° and V = 1180.05(18) Å3. The crystal structure of NH4MgCl3·6H2O was refined to R1 = 0.078 (wR2 = 0.185) on the basis of 1678 unique reflections. The (NH4)2Fe3+Cl5·H2O phase is orthorhombic, space group Pnma, unit cell parameters a = 13.725(2), b = 9.9365(16), c = 7.0370(11) Å and V = 959.7(3) Å3. The crystal structure of (NH4)2Fe3+Cl5·H2O was refined to R1 = 0.023 (wR2 = 0.066) on the basis of 2256 unique reflections. NH4MgCl3·6H2O is stable up to 90 °C and then transforms to the less hydrated phase isotypic to β-Rb(MnCl3)(H2O)2 (i.e., NH4MgCl3·2H2O), the latter phase being stable up to 150 °C. (NH4)2Fe3+Cl5·H2O is stable up to 120 °C and then transforms to an X-ray amorphous phase. Hydrogen bonds provide an important linkage between the main structural units and play the key role in determining structural stability and physical properties of the studied phases. The mineral phases NH4MgCl3·6H2O and (NH4)2Fe3+Cl5·H2O are isostructural with natural minerals novograblenovite and kremersite, respectively.

Analysis of phase transition behavior of BaCeO3 with thermal analyses and high temperature X-ray diffraction

2009 ◽  
Vol 180 (17-19) ◽  
pp. 1034-1039 ◽  
Author(s):  
Takeshi Ohzeki ◽  
Shinya Hasegawa ◽  
Misa Shimizu ◽  
Takuya Hashimoto
Keyword(s):  
Phase Transition ◽  
High Temperature ◽  
Thermal Analyses ◽  
X Ray Diffraction ◽  
Phase Transition Behavior ◽  
X Ray ◽  
Transition Behavior

Electrochemical Performance of La0.7Sr0.3Cu1-xFexO3-δ as Cathode Material in IT-SOFCs

2010 ◽  
Vol 160-162 ◽  
pp. 666-670
Author(s):  
Min Zhang Zheng ◽  
Xiao Mei Liu
Keyword(s):  
Electrical Conductivity ◽  
High Temperature ◽  
Cathode Material ◽  
Single Phase ◽  
Cathodic Polarization ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cathodic Overpotential ◽  
A Current

To obtain more detail information about the cathode of La0.7Sr0.3Cu1-xFexO3-δ（x= 0.1,0.3,0.5,0.7,0.9）in IT-SOFCs, the cathode material La0.7Sr0.3Cu1-xFexO3-δ（x=0.1, 0.3, 0.5, 0.7, 0.9）was synthesized by a sol-gel method. X-ray diffraction revealed it to be form a single phase of perovskite. The high temperature electrical conductivity was measured by using the four-point dc technique, and cathodic overpotential with SDC（Sm0.15Ce0.85O1.925） electrolyte support was measured by using a current-interruption technique. The investigation of electrocheimical properties suggested that La0.7Sr0.3Cu0.7Fe0.3O3-δ has the highest electrical conductivity and the lowest cathodic polarization. Using La0.7Sr0.3Cu0.7Fe0.3O3-δ as cathode and 65%NiO/SDC as anode based on SDC electrolyte one can obtain higher current density and power density at intermediate temperatures, La0.7Sr0.3Cu0.7Fe0.3O3-δ is considered to be a possible cathode adapted to IT-SOFCs.

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