Dynamics and structure of TeO2polymorphs: model treatment of paratellurite and tellurite; Raman scattering evidence for new γ- and δ-phases

The joint lattice-dynamical model study of the vibrational and elastic properties of paratellurite (α-TeO2) and tellurite (β-TeO2) has been conducted. Emphasis was laid on the crystal chemistry aspects of Raman spectra of these lattices. Results were used to interpret the Raman spectra of two new polymorphs (γ and δ) of tellurium dioxide, and to clarify their relationships with the spectrum of pure TeO2glass.