Berlin 2015 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 59: Oxide and Insulator Surfaces: Structure, Epitaxy and Growth
O 59.9: Vortrag
Mittwoch, 18. März 2015, 17:00–17:15, MA 042
Infra-red and Raman frequencies of Co3O4 – an ab initio study — Andrii Titov1, •Dominik Legut2,3, and Lucie Obalova3 — 1Nanotechnology Centre — 2IT4Innovations Centre — 3Inst. Env. Techn., VSB–TU Ostrava, Ostrava, Czech Republic
Among well known catalyst for N2O decomposition belongs Co3O4. Since
this reaction has oxidation-reduction mechanism, the electronic properties of
Co3O4 represent important feature. We have calculated electronic structure
and lattice dynamics, i.e. atomic vibrations using first-principles
calculations. We determined Raman and infra-red frequencies of the phonon modes.
Our results were calculated using single electron framework within the density
functional theory. For the electronic exchange correlation the general gradient
approximation as parametrized by Perdew–Burke–Ernzerhof [1] was used. To
obtain the correct description of the insulating behaviour the Hubbard U
technique was used. The anti-ferromagnetic ordering and spin-orbit interaction
were also considered. Lattice vibrations were calculated using Phonopy package
[2]. The dependences of the band gap, infra-red and Raman frequencies on the
Coulomb interaction (Hubbard U) were revealed and compared with experimental data measured at the VSB-TU Ostrava.
The work was supported by the Grant Agency of the Czech Republic, project reg. No. 14-13750S.
References:
1. J.P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett. 77, 3865 (1996).
2. A. Togo, F. Oba, I. Tanaka, Phys. Rev. B 78, 134106 (2008).