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Local Distortion Induced Metal-to-Insulator Phase Transition in PrRu$_4$P$_{12}$

D. Cao·R. H. Heffner·F. Bridges·I. -K. Jeong·E. D. Bauer·W. M. Yuhasz·M. B. Maple
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Abstract

Extended X-ray Absorption Fine Structure (EXAFS) experiments have been carried out on PrRu$_4$P$_{12}$ and PrOs$_4$P$_{12}$ to study the metal-to-insulator (MI) phase transition in PrRu$_4$P$_{12}$. No Pr displacement was observed across the MI transition temperature from the EXAFS data. Instead, our EXAFS data clearly show that a Ru displacement is associated with this MI transition. The very high Debye temperature for the Ru-P bond ($Θ_D$=690 K) suggests that a slight rotation/displacement of relatively rigid RuP$_6$ octahedra leads to this small Ru displacement, which accompanies the MI transition at 62 K in PrRu$_4$P$_{12}$.

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D. Cao, R. H. Heffner, F. Bridges, I. -K. Jeong, E. D. Bauer, W. M. Yuhasz, M. B. Maple. 2004-08-31. Local Distortion Induced Metal-to-Insulator Phase Transition in PrRu$_4$P$_{12}$. https://doi.org/10.1103/physrevlett.94.036403

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