Magnetic, transport and electronic properties of CeAu1−xNixIn intermetallics

Abstract

Polycrystalline compounds CeAu1−xNixIn (x=0.2, 0.4, 0.6 and 0.8) and their La-based counterparts were investigated by means of X-ray diffraction, magnetic, electrical resistivity and X-ray photoelectron spectroscopy (XPS) measurements. All these materials crystallize in the hexagonal ZrNiAl-type structure. The CeAu1−xNixIn alloys with x⩽0.6 exhibit Curie–Weiss paramagnetism down to the lowest temperatures studied, while that with x=0.8 shows a magnetic behavior characteristic of intermediate valence systems. In all the alloys, the electrical transport is influenced by Kondo effect, which for x⩽0.4 transforms with decreasing temperature from incoherent to coherent scattering, while for larger x exhibits single-ion character in the entire temperature range investigated. The XPS data indicates sizable hybridization of the Ce-4f electrons with conduction band, with the average occupation factor of the 4f1 ground state systematically diminishing with increasing the Ni content.