Mössbauer Study of β-Mn Alloys with Iron and Tin–Weak Itinerant-Electron Antiferromagnetism of β-Mn Alloys–

Mössbauer experiment of 57 Fe and 119 Sn in β-Mn alloys has been made. About 80% of iron atonas occupy positions of site I and tin atonas occupy site II. The average hyperfine fields at 57 Fe and 119 Sn iatcrease as the lattice constant increases. The hyperfine field at 57 Fe in Mn 1- x Fe x is about 10kOe at 4.2 K for x >0.02. The isomer shift of iron is -0.23 mm/sec at 295 K. The iron atom has a small localized moment in β-Mn. A transfer of d electrons from impurities to the d band of Mn is concluded to be the most important source to induce the antiferromagnetism of β-Mn alloys with 3d-transition metal impurities. Néel temperatures of alloys with iron and tin are expressed by two main contributions, which are the effects of d-electron number and lattice expansion.