scholarly journals Crystal structure of spinel-type Li0.64Fe2.15Ge0.21O4

2016 ◽  
Vol 72 (4) ◽  
pp. 505-508 ◽  
Author(s):  
Günther J. Redhammer ◽  
Gerold Tippelt
Keyword(s):  
Crystal Structure ◽  
Mössbauer Spectroscopy ◽  
Title Compound ◽  
Mossbauer Spectroscopy ◽  
Type Material ◽  
Flux Growth ◽  
Spinel Type ◽  
Tetrahedral Sites ◽  
Trivalent State ◽  
Oxygen Parameter

Spinel-type Li0.64Fe2.15Ge0.21O4, lithium diiron(III) germanium tetraoxide, has been formed as a by-product during flux growth of an Li–Fe–Ge pyroxene-type material. In the title compound, lithium is ordered on the octahedralBsites, while Ge4+orders onto the tetrahedralAsites, and iron distributes over both the octahedral and tetrahedral sites, and is in the trivalent state as determined from Mössbauer spectroscopy. The oxygen parameteruis 0.2543; thus, the spinel is close to having an ideal cubic closed packing of the O atoms. The title spinel is compared with other Li- and Ge-containing spinels.

Decomposition of CO2 to carbon by H2-reduced Ni(II)- and Co(II)-bearing ferrites at 300 °C

1994 ◽  
Vol 9 (2) ◽  
pp. 462-467 ◽  
Author(s):  
T. Kodama ◽  
H. Kato ◽  
S.G. Chang ◽  
N. Hasegawa ◽  
M. Tsuji ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Mössbauer Spectroscopy ◽  
Spinel Structure ◽  
Mossbauer Spectroscopy ◽  
High Reactivity ◽  
Metal Substitution ◽  
Spinel Type ◽  
Mößbauer Spectroscopy ◽  
Xrd Studies ◽  
Different Levels

Ni(II)- and Co(II)-bearing ferrites with different levels of metal substitution have been studied for CO2 decomposition. Ni2+ and Co2+ have been substituted for Fe2+ or Fe3+ in magnetite with the spinel type of crystal structure up to 14% and 26% for the mole ratio of Ni2+ and Co2+ to the total Fe contents, respectively. The metal substitution was corroborated by Mössbauer spectroscopy and XRD studies. They were activated in a flow of H2 gas to form oxygen-deficient ferrites with the spinel structure retained. The oxygen-deficient M(II)-bearing ferrites have been found to show high reactivity toward CO2 decomposition to carbon at 300 °C. The reactivity increased with the level of metal substitution and activation. The oxygens of CO2 were incorporated into the spinel structure and carbon was deposited on the surface of the ferrites. The deposited carbon was visible on dissolution of the ferrites used. The rate of decomposition on H2-activated Ni(II)-bearing ferrite with the mole ratio of 14% was 30 times as high as that of H2-activated magnetite.

scholarly journals Synthesis and investigation of neptunium zirconium phosphate, a member of the NZP family: crystal structure, thermal behaviour and Mössbauer spectroscopy studies

2017 ◽  
Vol 46 (35) ◽  
pp. 11626-11635 ◽  
Author(s):  
D. M. Bykov ◽  
R. J. M. Konings ◽  
C. Apostolidis ◽  
A. Hen ◽  
E. Colineau ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Mössbauer Spectroscopy ◽  
Infrared Spectroscopy ◽  
Thermal Behaviour ◽  
Zirconium Phosphate ◽  
Mossbauer Spectroscopy ◽  
Rietveld Analysis ◽  
Mößbauer Spectroscopy ◽  
Spectroscopy Studies

We synthesized a new NZP-type neptunium zirconium phosphate Np0.29Zr2(PO4)3 and investigated it by Rietveld analysis, infrared spectroscopy and Mössbauer spectroscopy.

Crystal structure, magnetic properties and Mössbauer spectroscopy of NaCaFe3(PO4)4

2003 ◽  
Vol 358 (1-2) ◽  
pp. 36-41 ◽  
Author(s):  
M Hidouri ◽  
B Lajmi ◽  
A Wattiaux ◽  
L Fournes ◽  
J Darriet ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Mößbauer Spectroscopy

scholarly journals The role and position of iron in 0.8CaZrO3-0.2CaFe2O4

Nukleonika ◽  
2015 ◽  
Vol 60 (1) ◽  
pp. 147-150
Author(s):  
Jacek Szczerba ◽  
Edyta Śnieżek ◽  
Paweł Stoch ◽  
Ryszard Prorok ◽  
Ilona Jastrzębska
Keyword(s):  
Crystal Structure ◽  
Mössbauer Spectroscopy ◽  
Composite Structure ◽  
Mössbauer Effect ◽  
Room Temperature ◽  
Mossbauer Spectroscopy ◽  
Sintering Temperature ◽  
Iron Ions ◽  
Mossbauer Effect ◽  
Spectroscopy Analysis

Abstract The aim of the study was to characterize the 0.8CaZrO3-0.2CaFe2O4 composite structure with particular emphasis on the role and position of iron in the function of sintering temperature. The paper presents the results of 57Fe Mössbauer effect at room temperature. It was found that the increase of sintering temperature causes an increase in the amount of incorporated iron ions in the CaZrO3-crystal structure. Based on Mössbauer spectroscopy analysis, it was found that three different environments of Fe3+ ions were observed in the obtained materials. Two of them corresponded to CaFe2O4 phase and one was associated with the substitution of Zr4+ by Fe3+ in the CaZrO3 structure.

The layered iron phosphate KMgFe(PO4)2: Crystal structure, Mössbauer spectroscopy and ionic conductivity

2009 ◽  
Vol 180 (36-39) ◽  
pp. 1558-1563 ◽  
Author(s):  
Abdessalem Badri ◽  
Mourad Hidouri ◽  
María Luisa López ◽  
María Luisa Veiga ◽  
Alain Wattiaux ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Mössbauer Spectroscopy ◽  
Ionic Conductivity ◽  
Mossbauer Spectroscopy ◽  
Iron Phosphate ◽  
Mößbauer Spectroscopy
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