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arXiv · 0712.1626

Thermoelectric properties of LaRh$_{1-x}$Ni$_x$O$_3$

S. Shibasaki·Y. Takahashi·I. Terasaki
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Abstract

We report measurements and analyses of resistivity, thermopower, and thermal conductivity of polycrystalline samples of perovskite LaRh$_{1-x}$Ni$_x$O$_3$. The thermopower is found to be large at 800 K (185 $μ$V/K for $x=$0.3), which is ascribed to the high-temperature stability of the low-spin state of Rh$^{3+}$/Rh$^{4+}$ ions. This clearly contrasts with the thermopower of the isostructural oxide LaCoO$_3$, which rapidly decreases above 500 K owing to the spin-state transition. The spin state of the transition-metal ions is one of the most important parameters in oxide thermoelectrics.

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S. Shibasaki, Y. Takahashi, I. Terasaki. 2009-02-12. Thermoelectric properties of LaRh$_{1-x}$Ni$_x$O$_3$. https://arxiv.org/abs/0712.1626

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