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

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 نشر من قبل Soichiro Shibasaki
 تاريخ النشر 2009
  مجال البحث فيزياء
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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 $mu$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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