Sökning: "electronic structure"

Visar resultat 26 - 30 av 1537 avhandlingar innehållade orden electronic structure.

  1. 26. 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

  3. 27. Parallelization of dynamic algorithms for electronic structure calculations

    Författare :Anton G. Artemov; Emanuel H. Rubensson; Maya Neytcheva; Bo Kågström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; parallelization; task-based programming; matrix algorithms; sparse matrices; inverse factorization; localized computations; density matrix methods; electronic structure calculations; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : The aim of electronic structure calculations is to simulate behavior of complex materials by resolving interactions between electrons and nuclei in atoms at the level of quantum mechanics. Progress in the field allows to reduce the computational complexity of the solution methods to linear so that the computational time scales proportionally to the size of the physical system. LÄS MER

  4. 28. Electronic Structure Calculations of Point Defects in Semiconductors

    Författare :Andreas Höglund; Susanne Mirbt; Alison Mainwood; Uppsala universitet; []
    Nyckelord :Physics; electronic structure calculations; point defects; semiconductor; formation energy; equilibrium solubility limit; thermodynamic equilibrium concentration; transfer levels; negative-U; 110 surface; diffusion; activation energy; solar cells; Fysik;

    Sammanfattning : In this thesis point defects in semiconductors are studied by electronic structure calculations. Results are presented for the stability and equilibrium concentrations of native defects in GaP, InP, InAs, and InSb, for the entire range of doping conditions and stoichiometry. LÄS MER

  5. 29. Electronic and Molecular Surface Structures of Dye-Sensitized TiO2 Interfaces

    Författare :Maria Hahlin; Håkan Rensmo; Hans Siegbahn; Anders Sandell; Mats Göthelid; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photoelectron spectroscopy; Electron spectroscopy; Solar Cells; Dye; TiO2; Surface; Interface; Electronic structure; Molecular surface structure; coadsorbent; Physics; Fysik; Fysik; Physics;

    Sammanfattning : The dye-sensitized solar cell is a promising solar cell technology. In these systems the key process for light to electricity conversion is molecular in nature and is initiated in dye molecules adsorbed at a semiconducting surface. LÄS MER

  7. 30. Conjugated materials for organic electronic devices : photoelectron spectroscopy studies

    Författare :Wojciech Osikowicz; William R. Salaneck; Linköpings universitet; []
    Nyckelord :conjugated polymers; oligomers; electronic structure; photoelectron spectroscopy; UPS; XPS;

    Sammanfattning : Conjugated materials have attracted great attention since the discovery of high conductivity in donor and acceptor doped polyacetylene over two decades ago. The discoveries mentioned below caused, however, that the interest begun to shift towards their pristine semi-conducting state. LÄS MER