Pressure tuning of Fermi resonance was studied by Raman scattering in the high-pressure phase CO2-III and for some natural abundant isotopic species. The observed changes in the spectral features of the host crystal suggest that pressure strongly weakens FR and the transition from a two-phonon bound state to a two-phonon unbound state takes place in the 2v2 region between 30 and 40 GPa. It appears that the differences in FR of the isotopic species are mainly controlled by the frequency shifts introduced by the different isotopic masses.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering