Resistivity and magnetic-susceptibility studies in the RPd<SUB>2</SUB>Al<SUB>3</SUB> (R=La, Ce, Pr, Nd, and Sm) system

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