Magnetic, transport and thermal properties of δ-phase UZr₂

Polycrystals of hexagonal δ-phase UZr2 have been synthesised and studied by means of heat capacity, magnetic susceptibility, magnetisation, electrical resistivity, magnetoresistance, thermoelectric power, thermal conductivity measurements, for the first time, at temperatures from 1.8 to 300 K and in magnetic fields up to 8 T. The weak temperature dependence of the magnetic susceptibility and the small value of both Seebeck (0.75 μV/K at room temperature) and of the Sommerfeld coefficient (13.5 mJ mol−1 K−2) point to 5f-electrons in this material having a delocalised nature. The electrical resistivity and magnetoresistance indicate the presence of significant electronic disorder in δ-UZr2, consistent with the disorder in its crystal structure. Density functional theory calculations have been performed and compared to experimental results.