Updated references for the structural, electronic, and vibrational properties of TiO2(B) bulk using first-principles
Mouna Ben Yahia1, Frédéric Lemoigno, Thomas Beuvier
1Institut Charles Gerhardt Montpellier UMR 5253 CNRS-UM2-ENSCM-UM1 Université Montpellier 2, 34095 Montpellier, France.
Abstract:
To get updated references on the structural, electronic, and vibration properties of the metastable TiO(2)(B) compound, infrared and Raman spectra of TiO(2)(B) are computed within the density functional theory framework and all active modes are assigned. Phonons and their possible coupling with the macroscopic electric fields resulting from the long-range interactions of instantaneous local dipoles (due to nuclear vibrations) in polar solids are taken into account through supercell calculations and longitudinal optical-transversal optical splitting corrections. Full structural relaxations using conventional density functional theory and hybrid functionals with localized Gaussian-type orbitals or plane-wave basis sets reveal a similar deviation of the local Ti environment compared to the TiO(2)(B) structural refinements reported so far. Such deviations are shown to be significant from those computed for anatase using the same method, thus yielding distinguishable spectroscopic responses for the two polymorphs.
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