Antiferromagnetic to ferromagnetic transition of hexagonal (Mn1−xFex)3Ge

We have made X-ray and neutron diffraction experiments and magnetization measurements for a pseudo-binary system (Mn1−xFex)3Ge. Antiferromagnetism with a coliinear spin structure exists at intermediate composition in between a triangular antiferromagnetic region with x < 0.18 and the typical ferromagnetic region with x ≧ 0.3. A magnetic phase diagram of the system is proposed.