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Title: High-pressure behaviour of Cs{sub 2}V{sub 3}O{sub 8} fresnoite

Abstract

Crystal structure of Cs{sub 2}V{sub 3}O{sub 8} fresnoite (P4bm, Z=2) has been studied using single-crystal X-ray diffraction in a diamond anvil cell to 8.6 GPa at room temperature. Cs{sub 2}V{sub 3}O{sub 8} undergoes a reversible first-order phase transition at about 4 GPa associated with anomalies in the pressure dependencies of the lattice parameters and unit-cell volume but without any symmetry change. Both structures consist of layers of corner-sharing V{sup 5+}O{sub 4} tetrahedra and V{sup 4+}O{sub 5} tetragonal pyramids separated by the Cs{sup +} cations located between the layers. At low pressures, the compression has little effect on the polarity of the structure. Above 4 GPa, the pseudosymmetry with respect to the corresponding centrosymmetric space group P4/mbm abruptly increases. The effects of external pressure and of the A{sup +} cation substitution in the vanadate fresnoites A{sub 2}V{sub 3}O{sub 8} (A{sup +}: K{sup +}, Rb{sup +}, NH{sub 4}{sup +}, Cs{sup +}) are discussed. - Graphical abstract: Non-centrosymmetric Cs{sub 2}V{sub 3}O{sub 8} undergoes a reversible first-order phase transition at about 4 GPa associated with an abrupt change of the pseudosymmetry with respect to the centrosymmetric space group P4/mbm. Display Omitted - Highlights: • High-pressure behaviour of vanadate fresnoites depends on alkali metal cations.more » • The size of the alkali metal cation determines whether the high-pressure phase is centrosymmetric. • No incommensurate structures are observed upon compression.« less

Authors:
 [1]; ;  [2];  [3]
  1. Institute of Crystallography, RWTH Aachen University, 52066 Aachen (Germany)
  2. Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States)
  3. Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany)
Publication Date:
OSTI Identifier:
22584127
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 238; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALKALI METALS; CATIONS; CESIUM IONS; DIAMONDS; LATTICE PARAMETERS; LAYERS; MONOCRYSTALS; PHASE TRANSFORMATIONS; POTASSIUM IONS; PRESSURE RANGE GIGA PA; PRESSURE RANGE KILO PA; PRESSURE RANGE MEGA PA 10-100; RUBIDIUM IONS; SPACE GROUPS; TETRAGONAL LATTICES; VANADATES; VANADIUM IONS; X RADIATION; X-RAY DIFFRACTION

Citation Formats

Grzechnik, Andrzej, E-mail: grzechnik@xtal.rwth-aachen.de, Yeon, Jeongho, Zur Loye, Hans-Conrad, and Friese, Karen. High-pressure behaviour of Cs{sub 2}V{sub 3}O{sub 8} fresnoite. United States: N. p., 2016. Web. doi:10.1016/J.JSSC.2016.03.041.
Grzechnik, Andrzej, E-mail: grzechnik@xtal.rwth-aachen.de, Yeon, Jeongho, Zur Loye, Hans-Conrad, & Friese, Karen. High-pressure behaviour of Cs{sub 2}V{sub 3}O{sub 8} fresnoite. United States. doi:10.1016/J.JSSC.2016.03.041.
Grzechnik, Andrzej, E-mail: grzechnik@xtal.rwth-aachen.de, Yeon, Jeongho, Zur Loye, Hans-Conrad, and Friese, Karen. 2016. "High-pressure behaviour of Cs{sub 2}V{sub 3}O{sub 8} fresnoite". United States. doi:10.1016/J.JSSC.2016.03.041.
@article{osti_22584127,
title = {High-pressure behaviour of Cs{sub 2}V{sub 3}O{sub 8} fresnoite},
author = {Grzechnik, Andrzej, E-mail: grzechnik@xtal.rwth-aachen.de and Yeon, Jeongho and Zur Loye, Hans-Conrad and Friese, Karen},
abstractNote = {Crystal structure of Cs{sub 2}V{sub 3}O{sub 8} fresnoite (P4bm, Z=2) has been studied using single-crystal X-ray diffraction in a diamond anvil cell to 8.6 GPa at room temperature. Cs{sub 2}V{sub 3}O{sub 8} undergoes a reversible first-order phase transition at about 4 GPa associated with anomalies in the pressure dependencies of the lattice parameters and unit-cell volume but without any symmetry change. Both structures consist of layers of corner-sharing V{sup 5+}O{sub 4} tetrahedra and V{sup 4+}O{sub 5} tetragonal pyramids separated by the Cs{sup +} cations located between the layers. At low pressures, the compression has little effect on the polarity of the structure. Above 4 GPa, the pseudosymmetry with respect to the corresponding centrosymmetric space group P4/mbm abruptly increases. The effects of external pressure and of the A{sup +} cation substitution in the vanadate fresnoites A{sub 2}V{sub 3}O{sub 8} (A{sup +}: K{sup +}, Rb{sup +}, NH{sub 4}{sup +}, Cs{sup +}) are discussed. - Graphical abstract: Non-centrosymmetric Cs{sub 2}V{sub 3}O{sub 8} undergoes a reversible first-order phase transition at about 4 GPa associated with an abrupt change of the pseudosymmetry with respect to the centrosymmetric space group P4/mbm. Display Omitted - Highlights: • High-pressure behaviour of vanadate fresnoites depends on alkali metal cations. • The size of the alkali metal cation determines whether the high-pressure phase is centrosymmetric. • No incommensurate structures are observed upon compression.},
doi = {10.1016/J.JSSC.2016.03.041},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 238,
place = {United States},
year = 2016,
month = 6
}
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