Synchrotron radiation 57Fe-M?ssbauer spectroscopy using nuclear monochromator

Formation of LaFeO₃ nanoparticles obtained from thermal decomposition of organometallic precursors was investigated as a function of the heat-treatment temperature. The precursors heat-treated below 300°C were amorphous, but above 350°C a single-phase of nanocrystalline LaFeO₃ was formed. The LaFeO₃ nanoparticles showed the superparamagnetic behavior in both magnetization and M?ssbauer measurements. With increasing heat-treatment temperature, the crystallite size of LaFeO₃ nanoparticles was gradually increased. The quadrupole splitting and isomer shift of paramagnetic doublet pattern were affected by the growth of LaFeO₃ particles.