Crossover from Kondo lattice to antiferromagnetic ordering in the CeCu6−xSnx phase

Magnetic and electronic properties as well as Ce LIII X-ray absorption spectra of the CeCu6−xSnx (x=0, 0.25, 0.75 and 1) solid solutions have been studied. The crystal structure of this phase belongs to the CeCu6 structure type. The substitution of Cu by Sn leads to a gradual weakening of the Kondo-type interaction and a reinforcement of the RKKY interaction. The CeCu5.25Sn0.75 and CeCu5Sn alloys order antiferromagnetically at TN=4 and 10 K, respectively. The LIII spectra show a trivalent state of Ce in the alloys containing Sn.