Structure and magnetic properties of U2Fe3Ge

We have identified a new compound of composition U2Fe3Ge, which crystallises in the hexagonal, C14 Laves phase MgZn2 type structure. Fe and Ge occupy randomly the sites of the Zn sublattice. The lattice volume increases by about 4.3% compared to the parent cubic Laves phase compound UFe2. The magnetic properties of U2Fe3Ge have been probed by using magnetization, resistivity, heat capacity and 57Fe Moessbauer spectroscopy. The compound orders ferromagnetically near 55 K in a state which is magnetically weaker than in UFe2. The latter is inferred from a lower saturated magnetic moment and hyperfine field at the Fe site. Resistivity shows a T2 behaviour at low temperatures. Both the coefficient of the T2 term in the resistivity and the Sommerfeld coefficient, γ, in U2Fe3Ge ire slightly higher compared to that in UFe2. (authors)