Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Structure and Properties of the α-Cs2Mo2−xWxO7 Solid Solution. / Solodovnikov, S. F.; Zolotova, E. S.; Solodovnikova, Z. A. и др.
в: Journal of Structural Chemistry, Том 60, № 6, 01.06.2019, стр. 952-960.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
}
TY - JOUR
T1 - Structure and Properties of the α-Cs2Mo2−xWxO7 Solid Solution
AU - Solodovnikov, S. F.
AU - Zolotova, E. S.
AU - Solodovnikova, Z. A.
AU - Korolkov, I. V.
AU - Yudin, V. N.
AU - Uvarov, N. F.
AU - Plyusnin, P. E.
AU - Saranchina, E. M.
PY - 2019/6/1
Y1 - 2019/6/1
N2 - The tungsten substitution for molybdenum in cesium dimolybdate Cs2Mo2O7 with the formation of an α-Cs2Mo2−xWxO7 solid solution is studied, and its homogeneity region at 540 °C is found to reach 0 ≤ x ≤ 0.6. It is established that the volume of the monoclinic (pseudo-orthorhombic) unit cell and the solid solution melting point monotonically increase with increasing tungsten content, whereas the phase transition temperature to the orthorhombic phase remains practically constant and is ∼390 °C. The crystals of solid solutions with several compositions are obtained, their structure is determined, and the tungsten atoms are found to be mainly located in octahedral positions of the α-Cs2Mo2O7 structure. As a result of the phase transition at 390 °C the electrical conductivity of Cs2Mo2O7 increases approximately by two orders of magnitude reaching 1.2·10−4S/cm at 460 °C. Due to a large size of Cs+ ions and a high charge of molybdenum cations it is supposed that the charge carriers are oxygen anions. The calculation of bond valence sum (BVS) maps for possible positions of oxygen atoms in the α-Cs2Mo2O7 cell shows the formation of a 3D system of oxygen conductivity channels at boundary BVS isosurface values ≥ 2.13.
AB - The tungsten substitution for molybdenum in cesium dimolybdate Cs2Mo2O7 with the formation of an α-Cs2Mo2−xWxO7 solid solution is studied, and its homogeneity region at 540 °C is found to reach 0 ≤ x ≤ 0.6. It is established that the volume of the monoclinic (pseudo-orthorhombic) unit cell and the solid solution melting point monotonically increase with increasing tungsten content, whereas the phase transition temperature to the orthorhombic phase remains practically constant and is ∼390 °C. The crystals of solid solutions with several compositions are obtained, their structure is determined, and the tungsten atoms are found to be mainly located in octahedral positions of the α-Cs2Mo2O7 structure. As a result of the phase transition at 390 °C the electrical conductivity of Cs2Mo2O7 increases approximately by two orders of magnitude reaching 1.2·10−4S/cm at 460 °C. Due to a large size of Cs+ ions and a high charge of molybdenum cations it is supposed that the charge carriers are oxygen anions. The calculation of bond valence sum (BVS) maps for possible positions of oxygen atoms in the α-Cs2Mo2O7 cell shows the formation of a 3D system of oxygen conductivity channels at boundary BVS isosurface values ≥ 2.13.
KW - cesium
KW - crystallization
KW - dimolybdate
KW - ionic conductivity
KW - molybdenum
KW - structure
KW - substitution
KW - synthesis
KW - thermal properties
KW - tungsten
KW - CRYSTAL-STRUCTURE
KW - ION
KW - REFINEMENT
KW - CONDUCTIVITY
KW - GROWTH
KW - PROGRAM
UR - http://www.scopus.com/inward/record.url?scp=85068748969&partnerID=8YFLogxK
U2 - 10.1134/S002247661906009X
DO - 10.1134/S002247661906009X
M3 - Article
AN - SCOPUS:85068748969
VL - 60
SP - 952
EP - 960
JO - Journal of Structural Chemistry
JF - Journal of Structural Chemistry
SN - 0022-4766
IS - 6
ER -
ID: 20836304