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arXiv · 0901.4582

Magnetic, Thermal, and Transport Properties of Layered Arsenides BaRu2As2 and SrRu2As2

R. Nath·Yogesh Singh·D. C. Johnston
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Abstract

The magnetic, thermal and transport properties of polycrystalline BaRu2As2 and SrRu2As2 samples with the ThCr2Si2 structure were investigated by means of magnetic susceptibility chi(T), electrical resistivity rho(T), and heat capacity Cp(T) measurements. The temperature (T) dependence of rho indicates metallic character for both compounds with residual resistivity ratios rho(310 K)/rho(2 K) of 17 and 5 for the Ba and Sr compounds, respectively. The Cp(T) results reveal a low-T Sommerfeld coefficient gamma = 4.9(1) and 4.1(1) mJ/mol K^2 and Debye temperature Θ_D = 271(7) K and 271(4) K for the Ba and Sr compounds, respectively. The chi (T) was found to be diamagnetic with a small absolute value for both compounds. No transitions were found for BaRu2As2 above 1.8 K. The chi(T) data for SrRu2As2 exhibit a cusp at \sim 200 K, possibly an indication of a structural and/or magnetic transition. We discuss the properties of BaRu2As2 and SrRu2As2 in the context of other ThCr2Si2-type and ZrCuSiAs-type transition metal pnictides.

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R. Nath, Yogesh Singh, D. C. Johnston. 2009-04-08. Magnetic, Thermal, and Transport Properties of Layered Arsenides BaRu2As2 and SrRu2As2. https://doi.org/10.1103/physrevb.79.174513

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