Dresden 2006 – wissenschaftliches Programm
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O: Oberflächenphysik
O 41: Electronic structure III
O 41.5: Vortrag
Donnerstag, 30. März 2006, 16:00–16:15, WIL B321
Reactivity of different V2O5 surfaces - cluster DFT studies — •Pawel Hejduk1, Malgorzata Witko1, and Klaus Hermann2 — 1Institute of Catalysis and Surface Chemistry, PAS, Cracow, Poland — 2Fritz-Haber Institut der MPG, Berlin, Germany
The wide application of vanadium oxides as catalysts follows from the fact that their crystallites may exhibit two structurally different types of faces: surfaces built of chemically saturated atoms and those built of unsaturated cations and anions. Both show different behavior in catalytic reactions by performing a complex multi-step operation on the reacting molecule through activation of some of the reactant bonds and hindering those interactions which could result in unwanted product. In this study the reactivity of saturated (010) and unsaturated (001) and (100) surfaces is determined by ab initio DFT cluster methods where electron exchange and correlation is approximated by the gradient corrected RPBE functional. Detailed electronic structure analyses are performed using Mulliken populations and Mayer bond indices, electrostatic potentials, total and partial (atom projected) densities-of-states. Further, adsorption of one and two hydrogen atoms as an atomic/molecular probe at the different surfaces, which leads to surface OH and H2O or two OH species, will be discussed in detail.