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arXiv · 2401.01205

Rattling Phonon Modes in Quadruple Perovskites

Z. V. Pchelkina·E. V. Komleva·V. Yu. Irkhin·Y. Long·S. V. Streltsov
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Abstract

Rattling phonon modes are known to be origin of various anomalous physical properties such as superconductivity, suppression of thermal conductivity, enhancement of specific heat etc. By means of DFT+$U$ calculations we directly show presence of the rattling mode in the quadruple perovskites CuCu$_3$V$_4$O$_{12}$ and CuCu$_3$Fe$_2$Re$_2$O$_{12}$ and argue that this can develop in others as well. It is demonstrated that Cu ions at $A$ sites vibrate in the center of the icosahedral oxygen O$_{12}$ cages and the corresponding potential has a complicated form with many local minima.

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Z. V. Pchelkina, E. V. Komleva, V. Yu. Irkhin, Y. Long, S. V. Streltsov. 2024-01-02. Rattling Phonon Modes in Quadruple Perovskites. https://doi.org/10.1134/s0021364023603202

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