Pressure-Induced Structural and Electronic Transition in Sr2ZnWO6 Double Perovskite.
High-pressure structural and electrical properties of Sr2ZnWO6 double perovskite were investigated using in situ angle-dispersive synchrotron X-ray diffraction (XRD), Raman, and alternating current (AC) impedance spectroscopy. A structural transition from monoclinic (P21/n) to triclinic (P1̅) phase around 9 GPa was observed due to the pressure-induced distortion of (W, Zn)O6 octahedron. In situ high-pressure Raman spectroscopy showed the increasing interaction among O-W-O in WO6 octahedron with pressure and a transition pressure consistent with the XRD results. From the AC impedance spectroscopy measurements, the resistivity increased steeply by ∼1 order of magnitude around 11 GPa, indicating an electronic transition accompanying the symmetry change. The increase in the interaction among O-W-O enhances the attraction of O(2-) electrons toward W(6+), thus increasing the covalence, which in turn lowers the charge transfer energy between O(2-) and W(6+) and induces the resistivity increase under high pressure.
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.
Nana
N
Li
Universite Hassan 1er , Laboratoire des Sciences des Matériaux, des Milieux et de la modélisation (LS3M), 25000, Khouribga, Morocco.
Bouchaib
B
Manoun
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.|High Pressure Synergetic Consortium, Geophysical Laboratory, Carnegie Institution of Washington , Argonne, Illinois 60439, United States.
Lingyun
L
Tang
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.
Feng
F
Ke
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.|The state Key Laboratory of Surface Physics, Department of Physics, and Laboratory of Advanced Materials, Fudan University , Shanghai 200433, China.
Fengliang
F
Liu
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.|Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences , Guizhou 550081, China.
Haini
H
Dong
Department of Earth Sciences, Uppsala University , SE-752 36 Uppsala, Sweden.
Peter
P
Lazor
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, China.|High Pressure Synergetic Consortium, Geophysical Laboratory, Carnegie Institution of Washington , Argonne, Illinois 60439, United States.
Wenge
W
Yang