Magnetic Properties of Intermetallic Compounds in Iron-Germanium System : Fe1.67Ge and FeGe2

The magnetic properties of the two intermetallic compound β phase (Fe 1.67 Ge) and δ phase (FeGe 2 ), in Fe-Ge system, were investigated. The β phase has B8 2 type of crystal structure and is ferromagnetic with the Curie point 485°K, saturation magnetization at 0°K 1.59 µ B , and paramagnetic moment 3.14 µ B per iron atom. The δ phase has C16 type of crystal structure and exhibits a parasitic ferromagnetic behavior in which the Neel point, asymptotic Curie point, saturation magnetization at 0°K, and paramagnetic moment are 190°K, +90°K, 0.11 µ B , and 2.43 µ B , per iron atom respectively. Brief discussions on the magnetic structures were given.