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Metallic conductivity and a Ca substitution study of NaRh2O4 comprising a double chain system

K. Yamaura·Q. Huang·M. Moldovan·D. P. Young·X. L. Wang·E. Takayama-Muromachi
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Abstract

The metallic compound NaRh2O4 forms a full range solid solution to the insulating phase CaRh2O4. At a Na concentration of 0.25 moles per formula unit, we found an unexpected contribution to the specific heat at low temperature [K. Yamaura et al. Chem. Mater. 17 (2005) 359]. To address this issue, specific heat and ac and dc magnetic susceptibilities were additionally measured under a variety of conditions for the Na0.25 sample. A new set of data clearly indicate the additional specific heat is magnetic in origin; however, the magnetic entropy is fairly small (~1 % of Schottky term for a simple splitting doublet), and there is no other evidence to suggest that a magnetic phase transition is responsible for the anomalous specific heat.

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K. Yamaura, Q. Huang, M. Moldovan, D. P. Young, X. L. Wang, E. Takayama-Muromachi. 2005-08-01. Metallic conductivity and a Ca substitution study of NaRh2O4 comprising a double chain system. https://doi.org/10.1016/j.physb.2006.01.454

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