Magnetic ordering in hexagonal PrCuSi

We report on the first multi-parameter investigation of a well-characterized sample of PrCuSi. The crystal structure is hexagonal, with a unique lattice site for each of the 3 atoms. Specific heat measurements indicate long-range magnetic ordering, and data of magnetic susceptibility confirm a paramagnetic-to-antiferromagnetic type transition at T_N = 5.1 K, in contrast to what was claimed previously in exploratory work on this compound. There is a well-defined anomaly in the electrical resistivity ρ(T) at T _N, below which a spin-density-wave expression accurately accounts for ρ(T) according to AFM ordering. A field-driven instability of the ordered state is furthermore indicated by a sharp feature in ρ(B) at B ∼ 0.75 T.