Ferrimagnetism in γ-manganese sesquioxide (γ - Mn ₂O ₃) nanoparticles

Compared to other manganese oxides, characterizations of γ - Mn ₂O ₃ are rare for both nanoparticles and the bulk material. We produced γ -Mn ₂O ₃ nanoparticles with particle diameters ranging from 10 to 15 nm and investigated, for the first time, their magnetic properties. The X-ray diffraction pattern shows that γ - Mn ₂O ₃ nanoparticles possess a tetragonal structure with lattice constants of a = 5.790 Å and c = 9.402 Å, We observed a coercivity as high as ∼ 8000 Oe at 5 K and a phase transition from ferrimagnetic to paramagnetic at 39 K.