R3: High-pressure science and deep Earth’s material

[R3-12] Pressure dependence of magnetic properties and electrical resistivity of Mn_3-xFe_xO₄ solid solution

*Takamitsu Yamanaka¹, Saqib Rahman¹, Takanori Hattori², Kazuki Komatsu³, Naohisa Hirao⁴, Ho-kwang Mao¹ (1. High Press Sci and Tech Res Center, 2. Japan Atomic Energy Agency, 3. Tokyo University Geochemical Research , 4. Research &Utilization Division JASRI SPRING-8)

Keywords:Mn3-xFexO4 solid solution, neutron diffraction experiment, electrical conductivity measurement, magnetic transition, High-pressure physical property change

Neutron diffraction allows precise analysis of the Mn_3-xFe_xO₄ structure using coherent scattering lengths between Mn (–3.73 fm) and Fe (9.54 fm). Mn_3-xFe_xO₄ spinel transforms into postspinel at high pressure. X-ray Mössbauer experiments revealed the distribution of Fe²⁺and Fe³⁺. MnFe₂O₄ and Mn₂FeO₄ are ferrimagnetic and they show hyperfine structure but postspinel has paramagnetic character. Postspinel shows electrical conductivity enhancement from semiconductor to metallization under extreme conditions. Metallization is confirmed by DOS calculation.