Infrared spectra of La0.65BaxMnO3-delta oxides

The infrared spectra of La0.65BaxMnO3-delta (x = 0.35, 0.33 and 0.30) were investigated experimentally. The result shows that the sample La0.65Ba0.33MnO3.delta has the largest Curie temperature and the smallest resistivity and wave number of the stretching vibration mode of MnO6 octahedron at 300 K among the investigated samples. However, the absorption strength for the stretching vibration mode of MnO6 octahedron in La0.65Ba0.35MnO3-delta is stronger for paramagnetic phase than that for ferromagnetic phase, which may be connected with the reducing of the dynamic incoherent Jahn-Teller distortion below Curie temperature. In addition, the large shift of wave number for the stretching mode at the temperatures from 293 to 423 K has been observed in La0.65Ba0.35MnO3-delta which may be due to the increase of the Mn-O bond length with temperature increasing.