Magnetic and electrical properties of NdNiSn

Magnetization and resistivity measurements have been carried out on the equiatomic ternary compound NdNiSn in the temperature range 2–200 K. The compound crystallizes in the orthorhombic CeNiSn-type structure with space group Pna21Pna21. Magnetic susceptibility shows a distinct feature at TN=3TN=3 K (Néel temperature), typical of a phase transition from an antiferromagnetic to paramagnetic state. In the paramagnetic regime, the magnetic susceptibility obeys Curie–Weiss behavior yielding an effective magnetic moment μeff=3.32μBμeff=3.32μB at lower temperatures, and 3.88 μBμB at higher temperatures. The reduction in the magnetic moment at lower temperatures is attributed to a crystalline electric field (CEF) effect, while the slight excess of magnetic moment at high temperatures compared to that of the free Nd3+ ion (3.62 μBμB) indicates that only a very small magnetic moment, at most 0.3 μBμB, is induced at the Ni sites. The electrical resistivity exhibits metallic behavior and no anomaly is observed at the respective Néel temperature. Analysis of the resistivity data in terms of crystalline electric fields including s–d electron scattering reveals that the ground magnetic state for the Nd3+ ions is a doublet of J=±5/2J=±5/2 states, with a first exited doublet of J=±7/2J=±7/2 states having an energy splitting of 56 K, with the next exited multiplet 139 K above the ground levels. These results are in fairly good agreement with those reported in the literature based on magnetic susceptibility and heat capacity measurements.