Influence of manganese on the structure and magnetic properties of YFeO3 nanocrystal

High purity Mn doped YFeO3 nanocrystals were readily prepared by sol–gel combustion method, with citric acid as the fuel. The doping effect on the structure and magnetic properties was systematically studied. X-ray diffraction and TEM results indicate that the samples are well crystallized. Orthorhombic YFeO3 crystallites can be obtained when calcined at 800 °C. In YFe1−xMnxO3 system for x ≤ 0.2, hexagonal structure exists as metastable phase and the calcined temperature has to be elevated to obtain pure orthorhombic phase. Distortion of the crystal structure was also observed, with changes in lattice parameters. The antiferromagnetic coupling was effectively strengthened with increased Mn content. This is possibly originated from the structural distortion which gives rise to enhanced antiferromagnetic superexchange interaction between Fe3+–Fe3+ and Fe3+–Mn3+.