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arXiv · 0711.1782

Hyper-Raman scattering analysis of the vibrations in vitreous boron oxide

G. Simon·B. Hehlen·R. Vacher·E. Courtens
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Abstract

Hyper-Raman scattering has been measured on vitreous boron oxide, $v-$B$_2$O$_3$. This spectroscopy, complemented with Raman scattering and infrared absorption, reveals the full set of vibrations that can be observed with light. A mode analysis is performed based on the local D$_{3h}$ symmetry of BO$_3$ triangles and B$_3$O$_3$ boroxol rings. The results show that in $v-$B$_2$O$_3$ the main spectral components can be succesfully assigned using this relatively simple model. In particular, it can be shown that the hyper-Raman boson peak arises from external modes that correspond mainly to librational motions of rigid boroxol rings.

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G. Simon, B. Hehlen, R. Vacher, E. Courtens. 2007-11-12. Hyper-Raman scattering analysis of the vibrations in vitreous boron oxide. https://doi.org/10.1103/physrevb.76.054210

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