4F-CONDUCTION ELECTRON HYBRIDIZATION IN TERNARY CE-TM-AL COMPOUNDS

We present an investigation of Ce-TM-Al phase diagrams with TM = Ru, P d, Pt and Au. Several new compounds have been characterized by measure ments of the electrical resistivity rho(T), the dc susceptibility chi( T) and, in some cases, the specific heat C(T). We find that in the com pounds with TM=Ru, the hybridization strength between 4f and conductio n electrons is strong, leading in most compounds to an intermediate va lent (IV) state. By contrast, most of the investigated compounds with TM = Pd, Pt and Au order magnetically indicating a much weaker hybridi zation strength. However, some of the Pt and especially Pd compounds a re very near to the crossover from the magnetic to the non-magnetic re gime as deduced from a Kondo-type maximum in the resistivity and a lar ge electronic specific heat at low temperatures.