Journal Article

IMPULSE-2025-00093

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Metallization without Charge Transfer in CuReO$_{4}$ Perrhenate under Pressure

Mikhailova, D. (Corresponding author) ; Avdoshenko, S. M. ; Avdeev, M. ; Hanfland, M. ; Schwarz, U. ; Prots, Y. ; Sarapulova, A. ; Glazyrin, K. ; Dubrovinsky, L. ; Senyshyn, A.MLZ* ; Engel, J. ; Ehrenberg, H. ; Tsirlin, A. A.

2025
American Chemical Society Washington, DC

Please use a persistent id in citations: doi:10.1021/acs.inorgchem.4c05051

Abstract: Using high-pressure synchrotron X-ray diffraction combined with Raman spectroscopy and density-functional calculations, we determined the sequence of the pressure-induced transformations in CuReO4. At 1.5 GPa, the lattice symmetry changes from I41cd to I41/a with the transformation of isolated ReO4-tetrahedra into infinite chains of ReO6-octahedra. The second, isosymmetric transition at 7 GPa leads to the formation of a NbO2-type structure with the octahedral oxygen coordination for both Cu1+ and Re7+ cations. Both transitions are of the first order and accompanied by discontinuities in the unit-cell volume of 7 and 14%, respectively. Density-functional calculations predict the metallic state of the high-pressure NbO2-type phase of CuReO4, and this prediction is in-line with the disappearance of the Raman signal above 7 GPa and visual observations (darkness/reflection of the sample). This metallization is caused by the increased bandwidth of both Cu 3d and Re 5d bands without any significant charge transfer between Cu and Re. At ambient pressure, the crystal structure of CuReO4 is retained between 4 and 700 K (melting point), showing a negative thermal expansion along the c-axis and a positive expansion along the a-axis within the entire temperature range.

Keyword(s): Chemical Reactions and Advanced Materials (1st) ; Chemistry (2nd)

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Contributing Institute(s):

1. STRUCTURE (STRUCTURE)
2. SPODI (SPODI)

Experiment(s):

1. SPODI: High resolution powder diffractometer (SR8a)

Appears in the scientific report 2025

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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