Compression effect on structure of the Li-stabilized high-temperature phase of Mn3(VO4)2 with composition Li0.2Mn2.9(VO4)2 - Raman spectroscopic and X-ray diffraction investigations

2021 ◽  
Vol 870 ◽  
pp. 159418
Author(s):  
Swayam Kesari ◽  
Alka B. Garg ◽  
Oliver Clemens ◽  
Rekha Rao
1996 ◽  
Vol 52 (a1) ◽  
pp. C364-C364
Author(s):  
J. A. Guevara ◽  
S. L. Cuffini ◽  
Y. P. Mascarenhas ◽  
P. de la Presa ◽  
A. Ayala ◽  
...  

2018 ◽  
Vol 24 (S1) ◽  
pp. 2248-2249
Author(s):  
M. Ramírez-Cardona ◽  
M.P. Falcón-León ◽  
G. Luis-Raya ◽  
G. Mejía-Hernández ◽  
R. Arceo ◽  
...  

2013 ◽  
Vol 820 ◽  
pp. 71-74
Author(s):  
Xiao Hua Wang ◽  
Wei He ◽  
Ling Min Zeng

Binary compound Y3Fe29cannot be directly formed by rare earth Y and Fe and the third element M (non-iron transition elements) must be introduced to form ternary compound Y3(Fe,M)29. In this work, six alloys with compositions of the Y3Fe29-xCrx(x=1,2,3,4,5,6) were prepared and investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and differential thermal analysis (DTA). The study on the thermal stability of these compounds points to that the compoundY3(Fe,Cr)29is a high temperature phase and exists above 1100K. The alloys with single-phase of Y3(Fe,Cr)29was decomposed into Y2(Fe,Cr)17and Y(Fe,Cr)12annealed at high temperature 1100K.


2003 ◽  
Vol 58 (1) ◽  
pp. 155-158 ◽  
Author(s):  
Olaf Reckeweg ◽  
Cora Lind ◽  
Arndt Simon ◽  
J. Salvo

Abstract CuCN was investigated by chemical analysis, IR spectroscopy and powder X-ray diffraction. A high-temperature phase of CuCN was identified and structurally characterized by Rietveld refinement. HT-CuCN is isotypic to AgCN (R3m (No. 166), Z = 3, a = 597.109(8), c = 484.33(5) pm, Cu (3a), C/N (6c), z = 0.3915(10) at 77 K) with head-tail disorder of the cyanide anions.


1985 ◽  
Vol 63 (2) ◽  
pp. 324-328 ◽  
Author(s):  
M. Sunitha Kumari ◽  
Etalo A. Secco

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.


Author(s):  
Akira Yoshiasa ◽  
Tomotaka Nakatani ◽  
Akihiko Nakatsuka ◽  
Maki Okube ◽  
Kazumasa Sugiyama ◽  
...  

A high-temperature single-crystal X-ray diffraction study of a synthetic PbTiO3perovskite was carried out over the wide temperature range 298–928 K. A transition from a tetragonal (P4mm) to a cubic (Pm \bar 3 m) phase has been revealed near 753 K. In the non-centrosymmetricP4mmsymmetry group, the difference in relative displacement between Pb and O along thec-axis is much larger than that between Ti and O. The Pb and Ti cations contribute sufficiently to polarization being shifted in the opposite direction compared with the shift of O atoms. Deviation from the linear changes in Debye–Waller factors and bonding distances in the tetragonal phases can be interpreted as a precursor phenomenon before the phase transition. Disturbance of the temperature factorUeqfor O is observed in the vicinity of the transition point, whileUeqvalues for Pb and Ti are continuously changing with increasing temperature. The O site includes the clear configurational disorder in the cubic phase. The polar local positional distortions remain in the cubic phase and are regarded as the cause of the paraelectricity. Estimated values of the Debye temperature ΘDfor Pb and Ti are 154 and 467 K in the tetragonal phase and decrease 22% in the high-temperature phase. Effective potentials for Pb and Ti change significantly and become soft after the phase transition.


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