Sökning: "Doped clusters"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden Doped clusters.

  1. 1. Multicomponent Clusters/Nanoparticles : An Investigation of Electronic and Geometric Properties by Photoelectron Spectroscopy

    Författare :Chaofan Zhang; Olle Björneholm; Maxim Tchaplyguine; Svante Svensson; Gerd Ganteför; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Clusters; Nanoparticles; Alloy; Atmospheric chemistry; Alkali halide; Transition metals; X-ray Photoelectron spectroscopy; Polarizability; Core-shell; Sandwich structure; MAX-lab; BESSY II;

    Sammanfattning : Clusters/nanoparticles are aggregates of a “small” number of building blocks, atoms or molecules, ranging from two up to millions of atoms. Two main groups of clusters have been studied using photoelectron spectroscopy based on synchrotron radiation. LÄS MER

  3. 2. Photoelectron Spectroscopy on Atoms, Molecules and Clusters : The Geometric and Electronic Structure Studied by Synchrotron Radiation and Lasers

    Författare :Torbjörn Rander; Olle Björneholm; Gunnar Öhrwall; Maxim Tchaplyguine; Matthias Neeb; Uppsala universitet; []
    Nyckelord :Atomic and molecular physics; Free clusters; Electron spectroscopy; Doped clusters; Laser excitation; Alkali metals; Electronic structure; Geometric structure; X-ray photoelectron spectroscopy XPS ; Resonant Auger spectroscopy RAS ; Near-threshold x-ray absorption fine structure NEXAFS ; Ultraviolet photoelectron spectroscopy UPS ; Detuning; Ultra-fast dissociation UFD ; Sodium; Potassium; Oxygen; Bromomethane; Argon; Xenon; Krypton; Molecular field splitting; Core hole lifetime; Core excitation; Atom- och molekylfysik;

    Sammanfattning : Atoms, molecules and clusters all constitute building blocks of macroscopic matter. Therefore, understanding the electronic and geometrical properties of such systems is the key to understanding the properties of solid state objects. LÄS MER

  4. 3. Cluster model of disordered systems : application to doped semiconductors and a simple model polymer

    Författare :Rolf G. Riklund; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : In this thesis we study with an extended cluster model calculation the combined effect of disorder and electron-electron interaction on the electronic structure of doped semiconductors and a simple model polymer chain. First a one-band model using a Hartree calculation is compared to other authors result for the impurity band using less realistic Hamiltonians. LÄS MER

  5. 4. Low Temperature Structural and Property investigations in the Zn-Sb System

    Författare :Johanna Nylén; Sven Lidin; Jeff Snyder; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Thermoelectrics; Zinc antimmonides; Metal doped semiconductors; Chemistry; Kemi; oorganisk kemi; Inorganic Chemistry;

    Sammanfattning : Thermoelectric Zn4Sb3 has a randomly disordered crystal structure at room temperature and undergoes a reversible sequence of phase transitions, β-α-α’/α, at low temperatures. During the transformations interstitial Zn atoms and Zn vacancies present in the β-phase become increasingly ordered. LÄS MER

  7. 5. Novel room temperature ferromagnetic semiconductors

    Författare :Amita Gupta; KTH; []
    Nyckelord :;

    Sammanfattning : In today's information world, bits of data are processed bysemiconductor chips, and stored in the magnetic disk drives.But tomorrow's information technology may see magnetism (spin)and semiconductivity (charge) combined in one 'spintronic'device that exploits both charge and 'spin' to carry data (thebest of two worlds). LÄS MER