Physical properties of YbXCu4 (X = Ag, Au, Cd, Mg, Tl, and Zn) compounds

We report a systematic study of the face-centered-cubic compounds YbXCu4 (X = Ag, Au, Cd, Mg, Tl, and Zn), as well as their corresponding nonmagnetic analogues LuXCu4. X-ray diffraction, heat capacity, magnetic susceptibility , high-field magnetization, electrical resistivity, Hall effect, and L-III- edge absorption measurements have been performed. The compounds have Kondo temperatures that range from about 10 K to nearly 1000 K. Although the sing le-impurity Kondo model qualitatively describes the physical properties of these materials, the quantitative details are not well described and the qu ality of the fits varies strongly from compound to compound. Compound-to-co mpound variations in crystal-electric fields, effective valence, and the st rength of f-ligand hybridization effects, as well as the influence of intri nsic disorder, may help to explain these discrepancies. [S0163-1829(99)0720 9-4].