Sökning: "vacancy"

Visar resultat 16 - 20 av 117 avhandlingar innehållade ordet vacancy.

  1. 16. Ab-initio description of mono-vacancies in metals and alloys

    Författare :Lorand Delczeg; Levente Vitos; Ann E. Mattsson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Trough the following pages a comprehensive study of open structures will be shown, including mono-vacancy calculations and open surfaces. These are electronic structure calculations using density functional theory within the exact muffin tin method. LÄS MER

  3. 17. Studies of Single and Multiple Ionization Processes in Rare Gases and some Small Molecules

    Författare :Lage Hedin; Raimund Feifel; Dag Hanstorp; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik; Physics with spec. in Atomic; Molecular and Condensed Matter Physics;

    Sammanfattning : In this thesis various aspects of photoionization are investigated with respect to both single and multiple electron emission from atoms and molecules. The studies include both valence and core levels and involve transitions which leave the atoms or molecules in various charge states. LÄS MER

  4. 18. Combined Molecular Dynamics and Embedded-Cluster Calculations in Metal Oxide Surface Chemistry

    Författare :Björn Herschend; Kersti Hermansson; Micael Baudin; Joachim Sauer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; embedded-cluster; ab initio; molecular dynamics; metal oxide; ceria; magnesium oxide; adsorption; surface defect; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi;

    Sammanfattning : The development and improvement of the functionality of metal oxides in heterogeneous catalysis and other surface chemical processes can greatly benefit from an atomic-level understanding of the surface chemistry. Atomistic calculations such as quantum mechanical (QM) calculations and molecular dynamics (MD) simulations can provide highly detailed information about the atomic and electronic structure, and constitute valuable complements to experimental surface science techniques. LÄS MER

  5. 19. From the Electronic Structure of Point Defects to Functional Properties of Metals and Ceramics

    Författare :David Andersson; Börje Johansson; Pavel Korzhavyi; Benjamin Burton; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; first principles; ab initio; density functional theory; Calphad; point defects; diffusion; solid electrolytes; oxygen storage materials; Material physics with surface physics; Materialfysik med ytfysik;

    Sammanfattning : Point defects are an inherent part of crystalline materials and they influence important physical and chemical properties, such as diffusion, hardness, catalytic activity and phase stability. Increased understanding of point defects enables us to tailor the defect-related properties to the application at hand. LÄS MER

  7. 20. A Theoretical Treatise on the Electronic Structure of Designer Hard Materials

    Författare :Håkan Wilhelm Hugosson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; electronic structure; density functional theory; transition metal carbides; transition metal oxides; hard materials; designer materials; Fysik; Physics; Fysik; fysik; Physics;

    Sammanfattning : The subject of the present thesis is theoretical first principles electronic structure calculations on designer hard materials such as the transition metal carbides and oxides. The theoretical investigations have been made in close collaboration with experimental research and have addressed both bulk electronic properties and surface electronic properties of the materials. LÄS MER