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First evidence for charge ordering in NaV$_2$O$_5$ from Raman spectroscopy

M. J. Konstantinovic·Z. V. Popovic·A. N. Vasil'ev·M. Isobe·Y. Ueda
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Abstract

We argue on the basis of symmetry selection rules and Raman scattering spectra that NaV$_2$O$_5$ undergoes a charge ordering phase transition at T$_c$=34 K. Such a transition is characterized by the redistribution of the charges at the phase transition and corresponds to the change of the vanadium ions, from uniform V$^{4.5+}$ to two different V$^{4+}$ and V$^{5+}$ states. In the low temperature phase the V$^{4+}$ ions are forming a "zig-zag" ladder structure along the {\bf b}-axis, consistent with the symmetry of the P2/b space group.

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M. J. Konstantinovic, Z. V. Popovic, A. N. Vasil'ev, M. Isobe, Y. Ueda. 1999-07-15. First evidence for charge ordering in NaV$_2$O$_5$ from Raman spectroscopy. https://doi.org/10.1016/s0038-1098(99)00338-5

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