MAGNETIC AND TRANSPORT-PROPERTIES OF (LA,CE)NI2

The magnetic and transport properties of La0.922Ni2 and Ce0.935Ni2 are investigated in the temperature range 2T250 K. The magnetic measurements in a magnetic field H50 kG show an intrinsic paramagnetic behavior. They also reveal the existence of foreign magnetic impurities and of 46-nm nickel particles, in concentration less than 0.03%. These concentrations are so small that these defects cannot play any role in the formation of rare-earth vacancies (in concentration 57 at. %). An anomalous s-shaped rise of the resistivity has been observed, which we attribute to the existence of strong scattering of the Ni d conduction electrons by phonons, which dominates the spin scattering in both compounds. © 1990 The American Physical Society.