TEMPERATURE-DEPENDENCE OF THE RAMAN-SPECTRUM OF BARIUM PEROXIDE

The Raman spectra of barium peroxide (BaO2) in the O-O stretching regi on were studied at various temperatures between 22 and 850 degrees C i n both O-2 and He atmospheres. Although only one peroxide stretching b and is expected for the crystal symmetry, three Raman bands, which wer e assigned to peroxide ions in different crystal environments due to t he relative locations of oxide impurities, were observed at all temper atures. The temperature dependencies of the Raman frequencies, bandwid ths, and the absolute and partial intensities were investigated in det ail, and these were explained on the basis of the sample composition a nd structural changes.