Canted ferromagnetic structure of UNiGe in high magnetic fields

UNiGe adopts the orthorhombic TiNiSi-type of structure and exhibits in zero field two different antiferromagnetic structures. Both are noncollinear with significant a axis component. Magnetic measurements indicate two metamagnetic-like transitions with the field applied along the b or the c axis. Neutron diffraction studies in magnetic fields applied along the c axis reveal above the second metamagnetic-like transition a canted ferromagnetic structure. U magnetic moments of (formula presented) exhibit a ferromagnetic c axis component of (formula presented) and an antiferromagnetic a axis component of (formula presented) Observation of such a canted ferromagnetic structure in UNiGe provides strong evidence for presence of anisotropic exchange interactions. The fact that the a axis component cannot be well aligned above the second metamagneticlike transition indicates that the antiferromagnetic interaction between the a axis components is much stronger than between the others. © 2002 The American Physical Society.