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Defect structure and vibrational states in Eu-doped cubic gadolinium oxide
Alexey N Kislov1, Anatoly F Zatsepin1
1Institute of Physics and Technology, Ural Federal University, Ekaterinburg, Russia. a.n.kislov@urfu.ru.
Physical Chemistry Chemical Physics : PCCP
|October 22, 2020
Summary
Trivalent europium (Eu) impurities in gadolinium oxide (Gd2O3) significantly alter its structure and phonon spectrum. These Eu ions, at two distinct sites, cause the strongest Raman peak due to resonant vibrations in oxygen ions.
Area of Science:
- Solid State Physics
- Materials Science
- Computational Chemistry
Background:
- Gadolinium oxide (Gd2O3) is a material with potential applications.
- Trivalent europium (Eu) impurities can be incorporated into Gd2O3.
- Understanding impurity effects on material properties is crucial for technological advancement.
Purpose of the Study:
- To investigate the impact of trivalent Eu impurities at two crystallographic sites in cubic Gd2O3.
- To analyze the influence of these impurities on the lattice structure and phonon spectrum.
- To identify the origin of specific resonant vibrations and their contribution to Raman spectra.
Main Methods:
- Shell model for interatomic interactions.
- Cluster approach for calculating lattice structures and phonon densities of states.
- Green function method for determining resonant vibration frequencies.
Main Results:
- Europium ions occupy two non-equivalent crystallographic positions in Gd2O3.
- These impurities induce localized resonant vibrations.
- The strongest Raman peak is attributed to resonant vibrations involving oxygen ions near Eu impurities.
Conclusions:
- The presence and specific sites of Eu impurities critically affect the phonon spectrum of Gd2O3.
- Europium ions are responsible for the dominant resonant vibration modes observed.
- This detailed understanding aids in tailoring optical and vibrational properties of doped gadolinium oxide.
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