Sökning: "X-ray Absorption Spectroscopy"

Visar resultat 21 - 25 av 218 avhandlingar innehållade orden X-ray Absorption Spectroscopy.

1. 21. Angle-Dependent Electron Spectroscopy Studies of C60 Compounds and Carbon Nanotubes

   Författare :Joachim Schiessling; P. A. Brühwiler; J. Nordgren; Hans-Peter Steinrück; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; fullerenes; C60; K3C60; multi-walled carbon nanotubes; molecules; clusters; electron spectroscopy; synchrotron radiation; x-ray absorption; x-ray emission; molecular orbitals; charge transfer; electron correlation; surface physics; Fysik; Physics; Fysik;

   Sammanfattning : Fullerenes have been shown to constitute a prototypical building block for truly nanometer-sized devices and exotic nanounit-based materials, e.g., high-temperature superconductors. LÄS MER

3. 22. 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

4. 23. Photoelectron Spectroscopy of High Temperature Superconductors and Related Compounds

   Författare :Henrik Nylén; Synkrotronljusfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; egenskaper elektriska; supraledare; magnetiska och optiska ; magnetisk resonans; X-ray Absorption; Photoelectron Spectroscopy; Resonant Photoemission; Condensed matter:electronic structure; High Temperature Superconductors; Angle Resolved Photoemission; electrical; supraconductors; magnetic and optical properties; magnetic resonance; spectroscopy; spektroskopi; Kondenserade materiens egenskaper:elektronstruktur; relaxation; Fysicumarkivet A:1998:Nylén;

   Sammanfattning : In this thesis, the high temperature superconductors (HTSC) Ba0.6K0.4BiO3, La2CuO4+x, Bi2Sr2Ca1-xYxCu2O 8+d, Bi2Sr2CuO6+d as well as semiconducting Ba0.9K0. LÄS MER

5. 24. 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

7. 25. Time-dependent molecular properties in the optical and x-ray regions

   Författare :Ulf Ekström; Patrick Norman; Knut Faegri; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; molecular physics; x-ray spectroscopy; relativity; Computational physics; Beräkningsfysik;

   Sammanfattning : Time-dependent molecular properties are important for the experimental characterization of molecular materials. We show how these properties can be calculated, for optical and x-ray frequencies, using novel quantum chemical methods. LÄS MER