Reversible Structural Phase Transition in ZnV2O6 at High Pressures

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• 作者：Ruilian Tang ; Yan Li ; Nana Li ; Dandan Han ; Hui Li ; Yongsheng Zhao ; Chunxiao Gao ; Pinwen Zhu ; Xin Wang
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：May 22, 2014
• 年：2014
• 卷：118
• 期：20
• 页码：10560-10566
• 全文大小：552K
• 年卷期：v.118,no.20(May 22, 2014)
• ISSN：1932-7455

文摘

The structural and electrical properties of ZnV₂O₆ under high pressure have been studied using Raman spectroscopy, in situ angle dispersive X-ray diffraction (ADXRD), and alternating current (AC) impedance spectroscopy. The results of Raman spectra indicate that ZnV₂O₆ undergoes a reversible structural change around 16.6 GPa, as evidenced by the appearance of new peaks. The results of Rietveld refinements from in situ ADXRD data indicate that the monoclinic symmetry (C2/m) is retained up to 16.0 GPa and the C2 phase comes to coexist between 16.0 and 16.9 GPa. Above 16.9 GPa, the high-pressure phase can be distinguished only as the C2 structure. The transformation process from the C2/m phase to the C2 phase is mainly caused by the more distorted ZnO₆ octahedra and VO₆ octahedra at higher pressures. The equal bond distances Zn鈥揙2 and V鈥揙3 in the C2/m phase become unequal in the C2 phase. Furthermore, the measurements of the AC impedance spectroscopy of ZnV₂O₆ reveal obvious changes in its electrical transport properties at 14.1 GPa which could correspond to the observed phase transition in the Raman and ADXRD measurements. The combined analyses of experimental results suggest the occurrence of a reversible structural phase transition of ZnV₂O₆ around 16.0 GPa.