Magnetic properties of the FeMn1−xNixGe compounds

Abstract The crystal structure and magnetic properties of the FeMn 1− x Ni x Ge (0≤ x ≤1) compounds have been studied by room temperature X-ray powder diffraction and magnetometric measurements within the temperature interval of 5–400 K and for magnetic fields up to 5 T. All compounds crystallize in a hexagonal Ni 2 In-type crystal structure with space group P 6 3 / mmc and show ferromagnetic behavior. It has been found that the temperature of magnetic ordering ( T C ) increases nearly linearly with increasing Ni concentration from 163 K ( x =0) to 304 K ( x =0.4). Samples with x ≥0.8 are ferromagnetically ordered above 400 K. The concentration dependency of the saturation magnetization at 5 K ( M S ) shows a maximum of M S =2.81 μ B per formula unit for x =0.4.