Sökning: "metal-surfaces"

Visar resultat 11 - 15 av 78 avhandlingar innehållade ordet metal-surfaces.

  1. 11. Chemical Bonding of Hydrocarbons to Metal Surfaces

    Författare :Henrik Öström; Anders Nilsson; Phil Woodruff; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Adsorption; hydrocarbon; core-level; spectroscopy; Physics; Fysik;

    Sammanfattning : Using x-ray absorption spectroscopy (XAS), x-ray emission spectroscopy (XES) and x-ray photoelectron spectroscopy (XPS) in combination with density functional theory (DFT) the changes in electronic and geometric structure of hydrocarbons upon adsorption are determined. The chemical bonding is analyzed and the results provide new insights in the mechanisms responsible for dehydrogenation in heterogeneous catalysis. LÄS MER

  3. 12. Ultrafast Probing of CO Reactions on Metal Surfaces : Changes in the molecular orbitals during the catalysis process

    Författare :Jörgen Gladh; Henrik Öström; Nils Mårtensson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hetrogenous catalysis; CO; transition metals; Ultrafast probing; oxidation; desorption; dissociation; kemisk fysik; Chemical Physics;

    Sammanfattning : This thesis presents experimental studies of three different chemical reaction steps relevant for heterogeneous catalysis: dissociation, desorption, and oxidation. CO on single-crystal metal surfaces was chosen as the model systems. LÄS MER

  4. 13. Bonding and Desorption Mechanismsof CO on Metal Surfaces

    Författare :Jörgen Gladh; Henrik Öström; Mats Götelid; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bonding; Desorption; CO; Metal; kemisk fysik; Chemical Physics; fysik; Physics;

    Sammanfattning : I have investigated two different systems CO/Fe(100) and CO/Ru(0001), toobtain new information on the binding and desorption processes. The twodifferent systems have served as a model system, one for a static examination,CO on iron, and for the dynamic case, CO on ruthenium. LÄS MER

  5. 14. Calculations of Electronic Properties of Metal Surfaces and Superlattices

    Författare :Stella Papadia; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Investigations of some aspects of electronic properties of metal surfaces and superlattices are presented in this Thesis. The calculations are based on Density-Functional methods. The first topic is resonances at free-electron-like metal surfaces. LÄS MER

  7. 15. Models of Auger Neutralization and Tunneling at Metal Surfaces

    Författare :Tony Fondén; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis consists of a theoretical study of electron transfer at metal surfaces. It considers two types of electron transfer (electron tunneling and Auger neutralization) that both can be used as a spectroscopy to investigate the surface electronic structure. LÄS MER