Theoretical study of the enhanced paramagnetism inCeNix(x=1, 2, and 5)

Theoretical investigations of the paramagnetic compounds CeNi, ${\mathrm{CeNi}}_2$, and ${\mathrm{CeNi}}_5$ have been performed by means of electronic-structure calculations. It is shown that an itinerant picture of the 4f states of cerium can explain the enhanced susceptibilities of CeNi and ${\mathrm{CeNi}}_2$. The experimental observations that the induced magnetization in a magnetic field is well localized on the nickel atoms in ${\mathrm{CeNi}}_5$ and well localized on the cerium atoms in CeNi and ${\mathrm{CeNi}}_2$ can be easily understood from the calculated results. An overall good agreement with experiments is achieved for the magnetic properties for all three compounds. From a comparison with specific-heat measurements, a large mass enhancement due to heavy quasiparticles has to be inferred for both ${\mathrm{CeNi}}_2$ and CeNi.