Crystal structure, magnetic and electrical transport properties of UPS single crystals

The crystal structure of UPS was refined from single-crystal X-ray diffraction data to a residual of 0.032 for 10 variables and 336 structure factors. It is of the tetragonal ZrSiS type (space group P4/nmm) with the lattice parameters a 3.8064(5) A and c 7.981(2)A. The magnetic and electrical properties of UPS were measured on single crystals, within the temperature range 5-300 K. The compound orders ferromagnetically below 118 K, with the magnetic moments aligned along the c-axis. At 5 K, the ordered magnetic moment amounts to 1.07 μB per U atom. Both in the ordered and paramagnetic regions, UPS exhibits a huge magnetic anisotropy. Above Tc, the electrical resistivity of UPS decreases logarithmically with increasing temperature. Below 20 K, a p ∼ T2 dependence is observed. (author)