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arXiv · 0906.1745

Antiferromagnetic behavior in CeCo$_{9}$Ge$_{4}$

C. Gold·L. Peyker·E. -W. Scheidt·H. Michor·W. Scherer
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Abstract

We investigate the novel intermetallic ternary compounds \emph{R}Co$_{9}$Ge$_{4}$ with \emph{R} = La and Ce by means of $X$-ray diffraction, susceptibility and specific heat measurements. CeCo$_{9}$Ge$_{4}$ crystallizes in the space group ${I}$ 4/ ${mcm}$ and is characterized by the coexistence of two different magnetic sublattices. The Ce-based sublattice, with an effective moment close to the expected value for a Ce$^{3+}$-ion, exhibits a magnetically ordered ground state with $T_{\mathrm{N}}=12.5$ K. The Co-based sublattice, however, exhibits magnetic moments due to itinerant 3$d$ electrons. The magnetic specific heat contribution of the Ce-sublattice is discussed in terms of a resonance-level model implying the interplay between an antiferromagnetic phase transition and the Kondo-effect and an underlying Schottky-anomaly indicating a crystal field level scheme splitting into three twofold degenerated micro states ($\Delta_1 = 69$ K, $\Delta_2 = 133$ K).

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C. Gold, L. Peyker, E. -W. Scheidt, H. Michor, W. Scherer. 2009-06-09. Antiferromagnetic behavior in CeCo$_{9}$Ge$_{4}$. https://doi.org/10.1088/1742-6596/200/1/012049

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