MAGNETIC-BEHAVIOR IN A SERIES OF CERIUM TERNARY INTERMETALLICS - CE2T2IN (T=NI, CU, RB, PD, PT, AND AN)

A group Of ternary cerium compounds Ce2T2In (T=Ni, Cu, Rh, Pd, Pt, and Au) has been synthesized. As found from single-crystal and powder x-r ay-diffraction studies, all these phases crystallize in a primitive te tragonal structure of the Mo2FeB2 type. Magnetic measurements (magneti zation, de and ac susceptibility) have revealed the physical propertie s of these intermetallics to be mainly governed by the 4f-d hybridizat ion. Depending on the filling of the transition metal d band the groun d state in Ce2T2In changes from a nonmagnetic to a well localized magn etic regime. It was proved that Ce2Ni2In and Ce2Rh2In are intermediate -valence systems, Ce2Pt2In is a strongly temperature-dependent paramag net, whereas Ce2Cu2In, Ce2Pd2In, and Ce2Au2In order magnetically at lo w temperatures. Measurements of the electrical resistivity have corrob orated the intermediate-valence behavior in Ce2Ni2In and Ce2Rh2In. In turn, the resistivity of the remaining ternaries studied was found to be determined by an interplay of Kondo scattering and crystal-held eff ects. For Ce2Pt2In which behaves like a spin-fluctuating system due to strong Kondo-type interactions a nonmagnetic heavy-fermion ground sta te probably occurs.