AVS 51st International Symposium
    Surface Science Thursday Sessions
       Session SS1-ThA

Paper SS1-ThA8
The Adsorption of Bromobenzene on Periodically-Stepped and Flat NiO(100) Surfaces

Thursday, November 18, 2004, 4:20 pm, Room 210B

Session: Metal Oxides and Clusters IV: Oxide Surface Chemistry
Presenter: S.C. Petitto, University of Nebraska-Lincoln
Authors: S.C. Petitto, University of Nebraska-Lincoln
E.M. Malone, University of Nebraska-Lincoln
M.A. Langell, University of Nebraska-Lincoln
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Bromobenzene was adsorbed onto both stepped and flat NiO(100) surfaces to model surface defects relevant to heterogeneous chemical processes. Both surfaces were characterized using Auger electron (AES) and X-ray photoelectron (XPS) spectroscopies, low energy electron diffraction (LEED), and thermal desorption mass spectrometry (TDS). The stepped NiO(100) substrate was cut and polished at an angle vicinal to the (100) surface, resulting in monoatomic steps with 7-atom terraces. The LEED diffraction patterns show sharp diffraction features for both surfaces, and diffraction spot splitting correlating to appropriate terrace and step height dimensions for the stepped surface. Both substrates interact with bromobenzene at 120 K to produce first a molecularly adsorbed monolayer species and then a multilayer adsorbate state as the exposure is increased. The stepped NiO(100) surface has an additional TDS peak not observed for flat NiO(100) and which results in dissociation adsorption initiated by cleavage of the Br-C@sub 6@H@sub5@ bond. Bromine that remained on the surface appeared as nickel bromide.