Resistivity and magnetic-susceptibility studies in the RPd₂Al₃ (R=La, Ce, Pr, Nd, and Sm) system

Abstract

In this paper we report magnetic-susceptibility and resistivity studies on hexagonal RPd₂Al₃ (R=La, Ce, Pr, Nd, and Sm) compounds from 1.5 to 300 K. We observe that NdPd₂Al₃ shows antiferromagnetic ordering (AFM) at 6.5 K from the susceptibility and resistivity studies. On the other hand, PrPd₂Al₃ does not show any ordering down to 1.5 K but its susceptibility saturates below 15 K. The susceptibility measurements on CePd₂Al₃ reveal a peak at 2.8 K which is an indication of AFM in this compound. In addition, we have carried out resistivity and magnetization measurements on SmPd₂Al₃. Our resistivity studies show at least two magnetic transitions that are in agreement with the previous heat-capacity studies but unlike their resistivity measurements show only one transition at 12 K in the same compound. Further, the detailed measurements of magnetization (M) vs field (H) isotherms show evidence for two field-induced transitions in this compound at 2.5 K.