AC MAGNETIC-SUSCEPTIBILITY AND NEUTRON-DIFFRACTION EXPERIMENTS ON UP1-XSX SOLID-SOLUTIONS

The temperature variation of the AC susceptibility of UP1-xSx single c rystals evidences some transition not yet reported in the ferromagneti c range of composition 0.4 less than or equal to x less than or equal to 0.6. These transitions are also observed in resistivity measurement s. Neutron diffraction experiments show that they correspond to magnet ic moment reorientations from the [100] axis at high temperature towar ds the [110] direction at lower temperature. So, at a given temperatur e, when x increases, there is a continuity of the moment direction whe n going from the antiferromagnetic collinear or multiaxial state to th e ferromagnetic state.