Intermediate valence state of Ce in the novel quaternary compound CeRu2Sn2Zn18

Abstract A novel quaternary compound CeRu 2 Sn 2 Zn 18 has been synthesized by a self-flux method. The structural, magnetic, and transport properties have been studied using single crystal X-ray structural analysis and measurements of the electrical resistivity ρ , specific heat C , and magnetic susceptibility χ . The X-ray structural analysis reveals that CeRu 2 Sn 2 Zn 18 is an ordered variant of the CeCr 2 Al 20 - and ZrZn 22 -types, as found in the isostructural R T 2 Sn 2 Zn 18 ( R  = La, Ce, Pr, Nd, T  = Fe, Co, Ru). ρ shows no sign of a phase transition down to 2 K and is proportional to T 2 below 50 K. χ exhibits a broad peak near 100 K, and the values are on the order of 10 −3 emu/mol over a temperature range of 2–300 K. The electronic specific heat coefficient γ is found to be 69 mJ/K 2 mol, which is approximately seven-fold larger than that of the La analog. These findings indicate that CeRu 2 Sn 2 Zn 18 is in the intermediate valence state.