Influence of the Kondo effect on the Ce-ordered magnetic moment existing in the compounds rich in germanium (≥50 % at.) of the Ce-Ni-Ge system

The magnetic properties of RExTyXz intermetallic compounds, with RE Rare Earth or Actinide, T = 3d, 4d or 5d transition metal and X = Si, Ge or Sn, result from the interactions between the localized f electrons and the conduction electrons (competition between the demagnetising Kondo and the magnetic RKKY interactions). During the last decade, a lot of series of compounds were studied, like ternary compounds of type RET2X2, to show the influence of each atomic element on the various physical properties. En route to more systematic investigations, we have studied the Ce-Ni-Ge system (where 20 ternary compounds were taken in evidence) in order to determine the influence of chemical composition on the Ce-ground states. At our knowledge, this study is the first realised in a same phase diagram. (author)