IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Monday Sessions
       Session SS2-MoA

Paper SS2-MoA7
Small Molecule Adsorption on SrTiO@sub 3@ and CaTiO@sub 3@ Surfaces

Monday, October 29, 2001, 4:00 pm, Room 121

Session: Molecular Interactions with Oxide Surfaces
Presenter: K.F. Ferris, Pacific Northwest National Laboratory
Authors: K.F. Ferris, Pacific Northwest National Laboratory
L.-Q. Wang, Pacific Northwest National Laboratory
Correspondent: Click to Email
Interactions of water and formate with stoichiometric and defective on (001) MTiO3 surfaces (M=Ca, Sr) have been studied using semiempirical and first principles electronic structure calculations. Preliminary results for water interaction with (001) CaTiO 3 indicate weaker adsorption than TiO2 surfaces, consistent with experimental results. Though energetically similar, water adsorption on TiO2- and CaO-terminated CaTiO3 surfaces result in a distinctly different geometric arrangements due to the surface ox ygen atoms and the charge distribution of these acceptor sites. Stepped (001) CaTiO3 surfaces have oxygen sites with greater accessibility and lower coordination, and are predicted to have increased reactivity for H2O and HCOOH. Preliminary results for fo rmate interaction with (100) SrTiO3 indicate strong adsorption consistent with experimental results, but in a distinctly different geometric arrangement from the TiO2 surfaces due to absence of bridging oxygen sites. Further results will be discussed in terms of potential reaction mechanisms and correlations with ongoing experimental studies. This work was supported by the U.S. Department of Energy, Office of Science, Material Sciences Division, under contract DE-AC06-76RLO 1830.