Hyper-Raman and Raman scattering in paratellurite TeO2

Vincent Rodriguez (1) , Michel Couzi (1) , Frédéric Adamietz (1) , Guillaume Guery (1, 2, 3) , Thierry Cardinal (2) , Philippe Veber (2) , Kathleen Richardson (3) , Philippe Thomas (4)

1 ISM - Institut des Sciences Moléculaires
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
3 COMSET - School of Materials Science and Engineering
4 SPCTS-AXE3 - Axe 3 : organisation structurale multiéchelle des matériaux

Raman spectra of the tetragonal D4/4 structure of paratellurite TeO2 have been revisited avoiding anomalous polarization-selection-rules violations previously observed and due to optical activity. We present a complementary hyper-Raman scattering study of paratellurite. Wavenumber and symmetry assignments are given for all expected 21 Raman active optical branches, except one LO component (out of the eight expected TO-LO pairs) of the polar doublet E modes. Also, the four expected hyper-Raman active A2 (TO) modes have been observed. Moreover, we have observed a strong Kleinman-disallowed hyper-Rayleigh signal, which is tentatively assigned as a first evidence of hyper-Rayleigh optical activity.

Mots clés: Hyper-Raman; Hyper-Rayleigh; Phonon; TO-LO modes; Paratellurite

Domaines: Matériaux

Vincent Rodriguez, Michel Couzi, Frédéric Adamietz, Guillaume Guery, Thierry Cardinal, et al.. Hyper-Raman and Raman scattering in paratellurite TeO2. Journal of Raman Spectroscopy, 2013, 44 (5), pp.739-745. ⟨10.1002/jrs.4251⟩. ⟨hal-00823481⟩