Magnetic Properties of UFe2+x Prepared by Splat Cooling

Magnetic properties of uranium-based compounds are related to the character of the 5f electronic states, ranging between a localized character and itinerancy (see e.g. [1]). UFe2 is the first uranium compound reported to exhibit ferromagnetism [2]. The Curie temperature TC given by various authors differs in some extent, but remains in the vicinity of 160 K in most of cases (see [1] and references therein). The itinerant character of magnetism was deduced on the basis of suppression of TC and spontaneous magnetization μs by pressure [3]. Neutron-diffraction study [4] revealed that UFe2 involves both 3d and 5f magnetism. The main contribution to the spontaneous magnetization comes from Fe (0.60μB/Fe), while U spin and orbital moments practically compensate. The U–Fe phase diagram contains two intermediate phases, namely U6Fe (formed non-congruently, weakly paramagnetic, superconducting [1]), and UFe2. Amorphous U–Fe systems have been successfully prepared in the vicinity of the two