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arXiv · 1612.02505

Coexistence of magnetic order and valence fluctuations in the Kondo lattice system Ce$_2$Rh$_3$Sn$_5$

Monika Barbara Gamża·Roman Gumeniuk·Ulrich Burkhardt·Walter Schnelle·Helge Rosner·Andreas Leithe-Jasper·Andrzej Ślebarski
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Abstract

We report on the electronic band structure, structural, magnetic and thermal properties of Ce$_2$Rh$_3$Sn$_5$. Ce $L_{\mathrm{III}}$-edge XAS spectra give direct evidence for an intermediate valence behaviour. Thermodynamic measurements reveal magnetic transitions at $T_{\mathrm{N1}}\approx$ 2.9 K and $T_{\mathrm{N2}}\approx$ 2.4 K. Electrical resistivity shows behaviour typical for Kondo lattices. The coexistence of magnetic order and valence fluctuations in a Kondo lattice system we attribute to a peculiar crystal structure in which Ce ions occupy two distinct lattice sites. Analysis of the structural features of Ce$_2$Rh$_3$Sn$_5$, together with results of electronic band structure calculations and thermodynamic data indicate that Ce2 ions are in an intermediate valence state with the ground state electronic configuration close to 4$f^0$, whereas Ce1 ions are trivalent (4$f^1$) and contribute to the low temperature magnetic ordering. Thus, our joined experimental and theoretical investigations classify Ce$_2$Rh$_3$Sn$_5$ as a multivalent charge-ordered system.

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Monika Barbara Gamża, Roman Gumeniuk, Ulrich Burkhardt, Walter Schnelle, Helge Rosner, Andreas Leithe-Jasper, Andrzej Ślebarski. 2016-12-08. Coexistence of magnetic order and valence fluctuations in the Kondo lattice system Ce$_2$Rh$_3$Sn$_5$. https://doi.org/10.1103/physrevb.95.165142

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