Possible correlated-electron behavior from quadrupolar fluctuations in PrInAg2

The temperature dependent magnetic susceptibility; specific heat, and electrical resistivity were measured on PrInAg2. A broad peak, which is identified as a Kondo anomaly, is observed in the specific heat at similar to 0.4 K with a strongly enhanced linear contribution at lower temperatures. PrInAg2 is a Pr-based heavy-fermion compound and has one of the largest known Sommerfeld coefficients of similar to 6.5 J/mol K-2. A new type of nonmagnetic interaction between the conduction electrons and the non-Kramers doublet ground state of the Pr3+ ion be responsible for this behavior. Related features are also observed in the susceptibility and resistivity.