Structural, electrical, magnetic and low-temperature specific heat studies of PrPb2

Investigations of the structure, the electrical resistivity, the magnetic properties and the low-temperature specific heal of PrPb2 have been made, The crystal structure identified by X-ray diffraction for PrPb2 is the body-centered tetragonal MoSi2-type structure with a=3.305 Angstrom and c=16.060 Angstrom. The magnetic part of the electrical resistivity for PrPb2 shows a -log T dependence similarly to that of CePb2, but its temperature region is not as wide as that of CePb2, The temperature derivative of the low-temperature magnetic electrical resistivity d rho(mag)/dT and the magnetic susceptibility show a broad peak around 6 K. The magnetic susceptibility exhibits Curie-Weiss behavior at high temperatures, and the effective magnetic moment is 3.68 mu(B)/Pr-mol and practically equals the value of the free trivalent Pr3+ ion, A linear extrapolation in zero field of the C/T versus T-2 plot for low-temperature specific heat gives a large electronic specific heat coefficient gamma of 656 mJ.mol(-1).K-2. Such a large value may be attribute to a Schottky specific heat. The peak around 4.5 K is too small and too broad, compared with a peak representative of a magnetic phase transition. Furthermore,, this peak is apparently reduced by applied magnetic fields. Therefore, the peaks observed in the magnetic susceptibility and the specific heat are not correlated with the Neel temperature. (C) 1998 Elsevier Science S.A.