RAMAN-SPECTRA OF MGSIO3-CENTER-DOT-10-PERCENT AL2O3-PEROVSKITE AT VARIOUS PRESSURES AND TEMPERATURES

Variations of Raman spectra of MgSiO3 . 10% Al2O3-perovskite were inve stigated up to about 270 kbar at room temperature and in the range 108 -425 degrees K at atmospheric pressure. Like MgSiO3-perovskite, the Ra man frequencies of MgSiO3 . 10% Al2O3-perovskite increase nonlinearly with increasing pressure and decrease linearly with increasing tempera ture within the experimental uncertainties and the range investigated. A comparison of these data with those of MgSiO3-perovskite suggests t hat MgSiO3 . 10% Al2O3-perovskite is slightly more compressible than M gSiO3-perovskite, and that the volume thermal expansion for MgSiO3 . 1 0% Al2O3-perovskite is also slightly greater than that for MgSiO3-pero vskite.