PHYSICA B-CONDENSED MATTER, ss.887-889, 1999 (SCI-Expanded)
We report SQUID magnetometry studies of the susceptibility of NdTX (T = Cu Ag, Au; X = Sn, Pb) compounds in the temperature range 5 K less than or equal to T less than or equal to 300 K and the field range 0.5 Oe less than or equal to H less than or equal to 50.000 Oe. The susceptibility curves, X(T), for all samples except NdCuSn, exhibit a sharp peak at the Neel temperature, TN The analysis of chi(T) in the paramagnetic region by using Curie-Weiss law enables us to determine the magnetic moments localized on Nd ions mu(eff), the Curie paramagnetic temperature theta(p) and the temperature-independent susceptibility X,. Oscillatory behaviour has been observed in low-field chi(T) versus 1/T for NdCuPb and NdAgPb, from which results suggest a helical antiferromagnetic ordering probably due to an exchange interaction of RKKY-type and crystalline held effects. We also find that superconductivity and antiferromagnetism coexist at the temperatures below T similar to 7K for the samples including Pb. (C) 1999 Elsevier Science B.V. All rights reserved.