Magnetic-susceptibility and electrical-resistivity measurements on RPdSn (R=CeYb) compounds

Magnetic-susceptibility and electrical-resistivity measurements have been carried out on equiatomic ternary compounds, RPdSn (R=CeYb), in the temperature range 4.2 and 300 K. The compounds EuPdSn and YbPdSn have been synthesized. As-cast RPdSn (R=CeYb) compounds crystallize in the orthorhombic TiNiSi-type structure. However, on annealing at 950°C, Er- and Tm-containing compounds transform to hexagonal Fe2P-type structure. Magnetic-susceptibility measurements reveal that the compounds with R=Ce, Sm, Eu, Gd, Tb, Dy, and Er order antiferromagnetically with Néel temperatures (TN) of 7.5, 11, 13, 14.5, 23.5, 11.4, and 5.6 K, respectively. The compounds with R=Pr, Nd, Ho, and Tm are paramagnetic down to 4.2 K. Susceptibility of YbPdSn shows Curie-Weiss behavior between 300-150 K with eff=1.45B and deviates considerably from it below 150 K. The electrical resistivity of all these compounds exhibits metallic behavior and shows a sharp drop at the respective Néel temperatures. The TN of the RPdSn series does not follow de Gennes scaling and, instead, peaks at Tb. This behavior of TN can be understood on the basis of crystalline-electric-field effects.