ELECTRICAL-RESISTIVITY AND HALL-EFFECT STUDY OF UN1AL SINGLE-CRYSTALS

We report on resistivity, susceptibility and Hall-effect measurements in magnetic fields up to 10 T and temperatures from 2 to 300 K on single-crystal platelets oriented parallel or perpendicular to the hexagonal c axis. While the resistivity shows little anisotropy the Hall effect and the susceptibility are highly anisotropic with a pronounced maximum for B parallel-to c and a nearly temperature independent behavior for B perpendicular-to c. The Hall data are decomposed into normal and anomalous contributions and the results are discussed in the light of the substantial anisotropy of the U-U separation parallel and perpendicular to the c axis.