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arXiv · 1609.07161

Crystal structure and low-energy Einstein mode in ErV$_2$Al$_{20}$ intermetallic cage compound

Michał J. Winiarski·Tomasz Klimczuk
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Abstract

Single crystals of a new ternary aluminide ErV$_2$Al$_{20}$ were grown using a self-flux method. The crystal structure was determined by powder X-ray diffraction measurements and Rietveld refinement, and physical properties were studied by means of electrical resistivity, magnetic susceptibility and specific heat measurements. These measurements reveal that ErV$_2$Al$_{20}$ is a Curie-Weiss paramagnet down to 1.95 K with an effective magnetic moment $\mu_{eff}$ = 9.27(1) $\mu_B$ and Curie-Weiss temperature $\Theta_{CW}$ = -0.55(4) K. The heat capacity measurements show a broad anomaly at low temperatures that is attributed to the presence of a low-energy Einstein mode with characteristic temperature $\Theta_E$ = 44 K, approximately twice as high as in the isostructural 'Einstein solid' VAl$_{10.1}$.

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Michał J. Winiarski, Tomasz Klimczuk. 2016-09-22. Crystal structure and low-energy Einstein mode in ErV$_2$Al$_{20}$ intermetallic cage compound. https://doi.org/10.1016/j.jssc.2016.09.029

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