Search for dissertations about: "first-principles theory"

Showing result 11 - 15 of 176 swedish dissertations containing the words first-principles theory.

  2. 11. Structural stability of solids from first principles theory

    Author : Blanka Magyari-Köpe; KTH; []
    Keywords : density functional theory; electronic structure; high pressure; perovskite structure; phase transition; structural stability; geophysics; binary alloys; elastic constants;

    Abstract : .... READ MORE

  4. 12. Point defects and ion conduction in solid oxides: a first-principles case study of La2Zr2O7

    Author : Joakim Nyman; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; proton; self compensation; hydrogen economy; DFT; La2Zr2O7; acceptor doping; lanthanum zirconate; oxygen vacancy; SOFC; pyrochlore; point defect; trapping; computational methods; solid oxide; charge compensation; first principles; ion conduction; solid oxide fuel cell; ceramic electrolyte; defect cluster; fuel cell; hydrogen;

    Abstract : In the endeavor to attain a clean environment and sustainable energy consumption, the notion of a future hydrogen economy stands out as one of the grandest visions. Striving for this vision, a critical task lies in optimizing the performance of the fuel-cell devices responsible for extracting electric power from the energy stored in hydrogen molecules. READ MORE

  5. 13. First-principles investigations of planar defects

    Author : Lu Song; Levente Vitos; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Two types of planar defects, phase interface and stacking fault, are addressed in this thesis. The investigation is mainly carried out for stainless steels which are fundamental materials in modern society. For the phase interface, we investigate the metallic bcc/bcc and fcc/bcc phase interfaces. READ MORE

  6. 14. First-principles investigations of planar defects

    Author : Song Lu; Levente Vitos; Graeme Ackland; KTH; []
    Keywords : ;

    Abstract : Two types of planar defects, phase interface and stacking fault, are addressed in thisthesis. The first-principles exact-muffin orbitals method in combination with thecoherent-potential approximation is the main density functional theory (DFT) toolfor our studies. READ MORE

  7. 15. Kinetics of Nanoparticle Catalysis from First Principles

    Author : Mikkel Jørgensen; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Density functional Theory; Mean field approximation; Acetylene hydrogenation; Kinetic Monte Carlo; CO oxidation; Entropy; Methane oxidation; Heterogeneous catalysis; Kinetic modeling; Nanoparticles;

    Abstract : Modern society depends heavily on heterogeneous catalysis, which creates strong economical and environmental incentives to improve catalyst efficiency. Heterogeneous catalysts are often realized as metal nanoparticles (NPs) supported on oxide surfaces, and catalysts are traditionally developed by trial and error approaches. READ MORE