Sökning: "XES"

Visar resultat 1 - 5 av 17 avhandlingar innehållade ordet XES.

  1. 1. X-ray Spectroscopic Studies of Materials for Nuclear Technology

    Författare :Johan Vegelius; Sergei Butorin; Frank de Groot; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; XAS; XES; RIXS; amorphous; DOS; spectroscopy; actinides; copper; uranium; plutonium;

    Sammanfattning : X-ray spectroscopic experiments, including X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS), were performed in a large energy range (60-9000 eV) on a variety of systems, probing different elements and orbitals. The systems can preferably be divided into three groups: Actinides, copper systems and amorphous materials. LÄS MER

  2. 2. Computational studies of core level XPS satellites in transition metal systems : Department of Quantum Chemistry, Uppsala University

    Författare :Johnny Bustad; Högskolan i Gävle; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; adsorbates; shake-up; surface science; XPS; XES; INDO; model systems; Chemical physics; Kemisk fysik;

    Sammanfattning : Upon core ionization of a free molecule or a molecule adsorbed on a metal surface, higher binding energy satellites are observed, so called "shake-up" satellites, which can be viewed as valence excitations simultaneously to the creation of the core hole. In this thesis, theoretical studies of such core level XPS satellites in transition metal systems are presented, as well as cluster calculations of XES spectra, using the quantum mechanical INDO method. LÄS MER

  3. 3. Theoretical modeling of x-ray and vibrational spectroscopies applied to liquid water and surface adsorbates

    Författare :Mathias P. Ljungberg; Lars Pettersson; Shaul Mukamel; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; water; XAS; XES; IR; Raman; Chemical physics; Kemisk fysik; kemisk fysik; Chemical Physics;

    Sammanfattning : This thesis presents results of theoretical modeling of x-ray and vibrational spectroscopies applied to liquid water and to CO adsorbed on a Ni(100) surface. The Reverse Monte Carlo method is used to search for  water structures that reproduce diffraction, IR/Raman and x-ray absorption by fitting them to experimental data and imposed constraints. LÄS MER

  4. 4. 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

  5. 5. Surface reactions and chemical bonding in heterogeneous catalysis

    Författare :Henrik Öberg; Lars G. M. Pettersson; Philippe Sautet; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kemisk fysik; Chemical Physics;

    Sammanfattning : This thesis summarizes studies which focus on addressing, using both theoretical and experimental methods, fundamental questions about surface phenomena, such as chemical reactions and bonding, related to processes in heterogeneous catalysis. The main focus is on the theoretical approach and this aspect of the results. LÄS MER