RELAXATION EFFECT OF IR REFLECTANCE SPECTRA OF NANOCRYSTALLINE COMPOSITE OXIDES WITH THE PEROVSKITE STRUCTURE

After nanocrystalline powder materials of LaFe0.4Co0.6O3 and LaFe0.2Co 0.8O3 were compacted into pellets under 1.0 GPa pressure, it was found that their IR reflectance spectra possessed an obvious relaxation phe nomenon, and the phenomenon had good reproducibility. When the samples were irradiated by an IR lamp, an incandescent lamp and indoor ambien t light, the IR reflectance spectra relaxation effect also occurred to different extents. The above phenomenon was not observed for nanocrys talline materials of other compositions. The results indicate that the relaxation phenomenon relates to energy level transitions and vibrati on absorption processes of incomplete molecules with certain compositi ons.