Sökning: "X-ray photoelectron spectroscopy"

Visar resultat 11 - 15 av 313 avhandlingar innehållade orden X-ray photoelectron spectroscopy.

1. 11. Ab initio simulations of core level spectra : Towards an atomistic understanding of the dye-sensitized solar cell

   Författare :Ida Josefsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; multiconfigurational quantum chemistry; CASSCF calculations; core-level spectroscopy; x-ray photoelectron spectroscopy; x-ray absorption; resonant x-ray scattering; dye solar cells; transition metals; kemisk fysik; Chemical Physics;

   Sammanfattning : The main focus of this thesis is ab initio modeling of core level spectra with a high-level quantum chemical description both of the chemical interactions and of local atomic multiplet effects. In particular, the combination of calculations and synchrotron-based core-level spectroscopy aims at understanding the local structure of the electronic valence in transition metal complexes, and the details of the solvation mechanisms of electrolyte solutions, systems relevant for the dye-sensitized solar cell. LÄS MER

3. 12. Techniques and Application of Electron Spectroscopy Based on Novel X-ray Sources

   Författare :Stefan Plogmaker; Hans Siegbahn; Håkan Rensmo; Emma Springate; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High Harmonic Generation HHG; HELIOS; X-ray Beam Chopper; Dye-sensitized Solar Cell; Ultra High Vacuum UHV; Photoelectron Spectroscopy; Pump-Probe; XUV; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Sammanfattning : The curiosity of researchers to find novel characteristics and properties of matter constantly pushes for the development of instrumentation based on X-radiation. I present in this thesis techniques for electron spectroscopy based on developments of X-ray sources both in time structure and energy. LÄS MER

4. 13. Soft X-ray Scattering Dynamics Close to Core Ionization Thresholds in Atoms and Molecules

   Författare :Johan Söderström; Jan-Erik Rubensson; Lorenzo Avaldi; Uppsala universitet; []
   Nyckelord :Physics; Soft X-ray emission; Resonant inelastic X-ray scattering; Double excitations; Helium; X-ray-emission-threshold-electron coincidence; Fysik;

   Sammanfattning : In this Thesis studies of highly excited states in gas-phase atoms and molecules (He, Ne, N2, O2, N2O and CO2) using a variety of synchrotron-radiation based techniques are presented. The three techniques used most frequently are X-ray-emission-threshold-electron coincidence (XETECO), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) and they are all given a brief introduction. LÄS MER

5. 14. On Surface Characteristics and Microstructural Development of Soft Magnetic Composite Powder and Components

   Författare :Christos Oikonomou; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; X-ray photoelectron spectroscopy; compaction; annealing; X-ray diffraction; soft magnetic composites; high resolution scanning electron microscopy; surface layers; magnetic testing; powder metallurgy; depth profiling; electron backscatter diffraction; focused ion beam; thickness determination; energy dispersive X-ray spectroscopy; microstructure;

   Sammanfattning : Soft Magnetic Composite (SMC) products manufactured by traditional Powder Metallurgical (PM) techniques, are strong candidate materials for electromagnetic applications. Their advantages are based on cost and energy efficient production methods, shape complexity realization and uniquely uniform and isotropic three dimensional (3D) magnetic properties. LÄS MER

7. 15. Fingerprints of light-induced molecular transients : from quantum chemical models of ultrafast x-ray spectroscopy

   Författare :Jesper Norell; Michael Odelius; Sang-Kil Son; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; time-resolved x-ray spectroscopy; quantum chemistry; electronic structure; multi-configurational self-consistent field; density functional theory; molecular dynamics; Born-Oppenheimer dynamics; non-adiabatic dynamics; proton-transfer; charge-transfer; solvatization; Dyson orbital; teoretisk fysik; Theoretical Physics;

   Sammanfattning : Absorption of sunlight generates renewable electricity and powers the growth of plants, but also causes severe damage both to synthetic materials and biological tissue. The wildly varying outcomes of these light-induced processes are ultimately determined by much slighter differences in their underlying reaction pathways, induced by the transient properties of short-lived and miniscule molecules; a powerful approach to their detection and characterization is offered by ultrafast x-ray spectroscopy, with identification of spectral fingerprints and further guidance from quantum chemical models. LÄS MER