Physical properties and magnetic structure of a layered antiferromagnet PrPd_0.82Bi₂

We report the physical properties, crystalline and magnetic structures of singe crystals of a new layered antiferromagnetic (AFM) material PrPd_0.82Bi₂. The measurements of magnetic properties and heat capacity indicate an AFM phase transition at T_N～7 K. A large Sommerfeld coefficient of 329.23 mJ·mol^-1·K^-2 is estimated based on the heat capacity data, implying a possible heavy-fermion behavior. The magnetic structure of this compound is investigated by a combined study of neutron powder and single-crystal diffraction. It is found that an A-type AFM structure with magnetic propagation wavevector k =(0 0 0) is formed below T_N. The Pr³⁺ magnetic moment is aligned along the crystallographic c-axis with an ordered moment of 1.694(3) μ_B at 4 K, which is smaller than the effective moment of the free Pr³⁺ ion of 3.58 μ_B. PrPd_0.82Bi₂ can be grown as large as 1 mm×1 cm in area with a layered shape, and is very easy to be cleaved, providing a unique opportunity to study the interplay between magnetism, possible heavy fermions, and superconductivity.