Abstract
The vibrational properties of metastable Ca-GeO3 perovskite are investigated as a function of temperature using Raman scattering. Mode-assignments are derived from polarized spectra of optically oriented single crystals. Neither symmetry-breaking structural transformations nor soft-mode behavior is revealed in the Raman spectra between room temperature and 650° C. Only a small decrease in the local static octahedral tilt angles can be inferred from the Raman data over this temperature range. A Landau extrapolation of the lowest frequency Ag modes suggests that these modes become critical near 2000° C, a temperature that is above the extrapolated zero pressure melting point.
Original language | English (US) |
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Pages (from-to) | 215-223 |
Number of pages | 9 |
Journal | Physics and Chemistry of Minerals |
Volume | 18 |
Issue number | 4 |
DOIs | |
State | Published - Dec 1991 |
ASJC Scopus subject areas
- Materials Science(all)
- Geochemistry and Petrology