Sökning: "GW theory"

Visar resultat 1 - 5 av 21 avhandlingar innehållade orden GW theory.

  1. 1. Atomistic modelling of functional solid oxides for industrial applications : Density Functional Theory, hybrid functional and GW-based studies

    Författare :Cecilia Århammar; Rajeev Ahuja; Steven Louie; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; density functional theory; oxides; GW; Condensed matter physics; Kondenserade materiens fysik; Magnetism; Magnetism; Defects and diffusion; Defekter och diffusion;

    Sammanfattning : In this Thesis a set of functional solid oxides for industrial applications have been addressed by first principles and thermodynamical modelling. More specificially, measurable quantities such as Gibbs free energy, geometry and electronic structure have been calculated and compared when possible with experimental data. LÄS MER

  3. 2. First Principles Calculations of Electron Transport and Structural Damage by Intense Irradiation

    Författare :Carlos Ortiz; Olle Eriksson; Mattias Klintenberg; Richard A. London; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Condense matter theory; electronic structure; quasiparticles; GW theory; molecular dynamics; Boltzmann transport; electron transport; impact ionization; structural damage; dielectric response; structural biology; radiation detectors; scintillators; positron emission tommography; Electronic structure; Elektronstruktur; Semiconductor physics; Halvledarfysik; Biological physics; Biologisk fysik; Critical phenomena phase transitions ; Kritiska fenomen fasövergångar ; Functional materials; Funktionella material; Materiefysik; Physics of Matter;

    Sammanfattning : First principle electronic structure theory is used to describe the effect of crystal binding on radiation detectors, electron transport properties, and structural damage induced by intense irradiation. A large database containing general electronic structure results to which data mining algorithms can be applied in the search for new functional materials, a case study is presented for scintillator detector materials. LÄS MER

  4. 3. Electronic Structure and Optical Properties of Solar Energy Materials

    Författare :Baochang Wang; Natalia Skorodumova; Silvana Botti; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; GW; Bethe-Salpeter equation; Kinetic Monte Carlo; Density Functional Theory; Materials Science and Engineering; Teknisk materialvetenskap;

    Sammanfattning : In this thesis, we have studied the electronic and optical properties of solar energy m-terials. The studies are performed in the framework of density functional theory (DFT), GW, Bethe-Salpeter equation (BSE) approaches and Kinetic Monte Carlo (KMC). We present four sets of results. LÄS MER

  5. 4. Model Vertices Beyond the GW Approximation

    Författare :Mikael Hindgren; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Matematisk och allmän teoretisk fysik; thermodynamics; statistical physics; gravitation; GW approximation; Electron self energy; Green s function; consistency; local-field corrections; vertex function; conserving approximations; variational energies; Mathematical and general theoretical physics; classical mechanics; relativity; quantum mechanics; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Fysicumarkivet A:1997:Hindgren;

    Sammanfattning : We study the effects of local vertex corrections to the self energy of the electron gas. We find that a vertex derived from time-dependent density-functional theory can give accurate self energies without including the explicit time dependence of the exchange-correlation potential provided, however, that a proper decay at large momentum transfer (large q) is built into the vertex function. LÄS MER

  7. 5. Acceptor-doped barium zirconate: Oxidation, hydration and space-charge formation

    Författare :Anders Lindman; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; BaZrO3; space charge; point defects; oxidation; GW; hydration; density functional theory; grain boundaries; interatomic potential; perovskites;

    Sammanfattning : The current production and use of fossil fuels is not sustainable and new technologies are needed to become more independent of these fuels.The hydrogen economy, with the fuel cell as an efficient converter of chemical to electrical energy, is a desirable alternative.For this to become a reality, new materials with tailored properties are required. LÄS MER