Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 14: Oxide Surfaces: Adsorption and Reactivity
O 14.11: Vortrag
Montag, 16. März 2015, 17:30–17:45, MA 042
The interaction of water molecules with hematite(0001) surface — •Roman Ovcharenko and Elena Voloshina — Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Str. 2 12489 Berlin, Germany
The interaction of water with oxide surfaces is ubiquitous, as water is always present either as a reactant or just an "innocent spectator". The wetting process is predominantly govern by several factors, such as ambient conditions, surface termination and valence band structure. The precision ab initio calculation of the latter two properties of the α-Fe2O3 surface is a serious challenge posed to theory due to Fe 3d electrons, unusual hybridisation, huge surface relaxations, big super cells and magnetism. The situation becomes even more complicated since taking into account on-site Coulomb interactions drastically changing the structure of the valence band top, that allows anyone to consider hematite as charge-transfer insulator in contrary to the prediction of pure GGA approach.
In this study we present the detailed ab initio theoretical investigation of the single water molecule behaviour on the hematite(0001) surface. The electronic structure has been treated within DFT approach with PBE-GGA exchange-correlation functional. To take into account Fe 3d strong electronic correlation we adopt DFT+U approach formalised by Dudarev and D2 theory proposed by Grimme has been applied to account for dispersion interaction between water molecule and the surface termination.