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Nonadiabaticity in a Jahn-Teller system probed by absorption and resonance Raman scattering.
1Institute of Physics, University of Tartu, Riia 142, 51014 Tartu, Estonia.
The Journal of Chemical Physics
|March 22, 2013
Summary
This study presents a theory for light scattering in crystals with Jahn-Teller effects. It reveals how quantum effects and phonon interactions shape the observed spectra, crucial for understanding impurity centers.
Area of Science:
- Solid State Physics
- Quantum Chemistry
- Spectroscopy
Background:
- Impurity centers in crystals often exhibit complex electronic and vibrational interactions.
- The Jahn-Teller effect, particularly the E⊗e-type, significantly influences the excited states of these centers.
- Understanding light scattering phenomena like absorption and resonance Raman scattering is key to characterizing these systems.
Purpose of the Study:
- To develop a theoretical framework for absorption and resonance Raman scattering in crystals with E⊗e-type Jahn-Teller effects.
- To investigate the role of vibronic interactions with local/pseudolocal modes and phonon baths.
- To elucidate the emergence of specific quantum effects in the calculated spectra.
Main Methods:
- Theoretical modeling of vibronic interactions.
- Consideration of non-totally symmetric local/pseudolocal modes and phonon continua.
- Analysis of quantum effects including nonadiabaticity, size effects, scattering channel interference, and Fermi resonances.
Main Results:
- A theory for absorption and resonance Raman scattering is established for impurity centers with E⊗e-type Jahn-Teller effects.
- Specific quantum phenomena such as nonadiabaticity-induced enhancement, size effects, and Fermi resonances were identified.
- The crucial role of vibronic interaction with phonons in determining spectral structure was demonstrated.
Conclusions:
- The presented theory successfully describes absorption and resonance Raman scattering in the presence of Jahn-Teller effects.
- Quantum effects significantly influence the scattering spectra, providing insights into the system's dynamics.
- Phonon interactions are fundamental in shaping the observable spectral features of impurity centers.
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