Sökning: "density functional calculations"

Visar resultat 1 - 5 av 381 avhandlingar innehållade orden density functional calculations.

  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. Challenges in Enzyme Catalysis - Photosystem II and Orotidine Decarboxylase : A Density Functional Theory Treatment

    Författare :Marcus Lundberg; Margareta Blomberg; Per Siegbahn; Jeremy Harvey; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photosystem II; oxyl radical; manganese systems; orotidine decarboxylase; reaction mechanism; density functional theory; Quantum chemistry; Kvantkemi;

    Sammanfattning : Possibly the most fascinating biochemical mechanism remaining to be solved is the formation of oxygen from water in photosystem II. This is a critical part of the photosynthetic reaction that makes solar energy accessible to living organisms. LÄS MER

  4. 3. Density Functional Theory Calculations for Graphene-based Gas Sensor Technology

    Författare :Karim Elgammal; Anna Delin; Giuseppe Iannaccone; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; graphene; ab-initio; humidity; carbon dioxide; substrate; DFT; vdW; first-principle; simulation; calculations; Fysik; Physics;

    Sammanfattning : Nowadays, electronic devices span a diverse pool of applications, especially when getting smaller and smaller satisfying the more than Moore paradigm. To further develop this, studies focusing on material design toward electronic devices are crucial. LÄS MER

  5. 4. The many-electron energy in density functional theory : from exchange-correlation functional design to applied electronic structure calculations

    Författare :Rickard Armiento; Göran Grimvall; Jens K. Nörskov; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : Att förutsäga egenskaper hos material och kemiska system är en viktig komponent för teoretisk och teknisk utveckling i fysik, kemi och biologi. Ett systems egenskaper styrs till stor del av dess elektrontillstånd. Datorprogram som baseras på täthetsfunktionalsteori kan beskriva elektronkonfigurationer mycket noggrant. LÄS MER

  7. 5. Density Functional Theory in Computational Materials Science

    Författare :Jorge Mario Osorio Guillén; Rajeev Ahuja; Börje Johansson; Bruce N. Harmon; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Density Functional Theory; High Pressure; Phase Transitions; Elastic Properties; Lithium Batteries; Dilute Magnetic Semiconductors; Fysik; Physics; Fysik;

    Sammanfattning : The present thesis is concerned to the application of first-principles self-consistent total-energy calculations within the density functional theory on different topics in materials science. Crystallographic phase-transitions under high-pressure has been study for TiO2, FeI2, Fe3O4, Ti, the heavy alkali metals Cs and Rb, and C3N4. LÄS MER