Abstrakt
Our report describes the anomalous electronic behavior of CeNixPd1-xIn compounds studied by specific heat and electrical resistivity measurements. These compounds belong to the large and relatively thoroughly studied group of ternary rare-earth intermetallics crystallizing in the ZrNiAl-type structure.
The investigated series shows a transition from the heavy fermion antiferromagnetic system of CePdIn to the valence fluctuating state observed in CeNiIn. The isostructural and isoelectronic substitution of Pd by Ni leads to a change in the character of the d-electrons and the lattice parameters of the system because of the smaller radius of Ni atoms.
These changes have a great impact on the magnetic properties of the studied compounds. The antiferromagnetic transition shifts first to lower temperatures, from T-N = 1.7 K for CePdIn to T-N = 1.3 K for CeNi0.2Pd0.8In.
For a Ni content >= 40%, there is no sign of a magnetic phase transition in the specific heat and electrical resistivity data. Moreover, the data indicate anomalous non-Fermi-liquid behavior for concentrations with 0.4 <= x <= 0.6, which is clearly seen in both types of measurements.
The rest of series behaves similarly to the second parent compound CeNiIn. Besides the cerium compounds, superconductivity in LaNi0.2Pd0.8In is also presented.