Sökning: "configurational energy"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden configurational energy.

  1. 1. First Principles Modelling of Clean Energy Materials

    Författare :Pjotrs Žguns; Natalia Skorodumova; Andrei Ruban; Susanne Mirbt; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DFT; energy; catalysis; ionic conductors; SOFC; adatom charging; anharmonicity; configurational energy; Materials Science and Engineering; Teknisk materialvetenskap;

    Sammanfattning : This licentiate thesis presents the density functional theory study on clean energy materials relevant for catalysis applications, and for solid oxide fuel cells.In the first part of the thesis the metal supported ultrathin films, namely ScN/Mo, MgO/Mo and NaF/Mo are considered, and the Cu atom adsorption and charging on them is explored. LÄS MER

  3. 2. Configurational and Magnetic Interactions in Multicomponent Systems

    Författare :Björn Alling; Igor A. Abrikosov; Lars Hultman; Stefan Blügel; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic interactions; Configurational thermodynamics; Curie temperature; theoretical physics; magnetism; TiAlN; TiN; AlN; CrN; TiCrN; nitrides; NiMnSb; NiCuMnSb; Heusler alloys; spintronics; half-metallic; spinodal decomposition; first-principles; ab-initio; Magnetism; Magnetism;

    Sammanfattning : This thesis is a theoretical study of configurational and magnetic interactions in multicomponent solids. These interactions are the projections onto the configurational and magnetic degrees of freedom of the underlying electronic quantum mechanical system, and can be used to model, explain and predict the properties of materials. LÄS MER

  4. 3. Configurational Thermodynamics of the CeO2-Gd2O3 System : A Combined DFT, Cluster Expansion and Monte Carlo Approach to Bulk and Interfaces

    Författare :Pjotrs A. Žguns; Natalia V. Skorodumova; Andrei V. Ruban; María Verónica Ganduglia-Pirovano; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this thesis, we study the configurational thermodynamics of Ce1-xGdxO2-x/2 x ≤ 1 or CGO. We apply a combined Density Functional Theory (DFT), cluster expansion and Monte Carlo (MC) approach in which the configurational energy of CGO is described by means of the Ising-type Hamiltonian. LÄS MER

  5. 4. Disordered Icosahedral Boron-Rich Solids : A Theoretical Study of Thermodynamic Stability and Properties

    Författare :Annop Ektarawong; Björn Alling; Michael Widom; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Icosahedral boron-rich solids; Boron carbide; Configurational disorder; First-principles calculations; Thermodynamic stability; Superatom-special quasirandom structure;

    Sammanfattning : This thesis is a theoretical study of configurational disorder in icosahedral boron-rich solids, in particular boron carbide, including also the development of a methodological framework for treating configurational disorder in such materials, namely superatom-special quasirandom structure (SA-SQS). In terms of its practical implementations, the SA-SQS method is demonstrated to be capable of efficiently modeling configurational disorder in icosahedral boron-rich solids, whiles the thermodynamic stability as well as the properties of the configurationally disordered icosahedral boron-rich solids, modeled from the SA-SQS method, can be directly investigated, using the density functional theory (DFT). LÄS MER

  7. 5. The effect of inelastic deformation on crack loading

    Författare :Dimosthenis Floros; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Numerical simulation; Mixed mode; Configurational mechanics; Gradient plasticity;

    Sammanfattning : Rolling contact fatigue (RCF) cracks in rails are among the most detrimental railway track defects, in relation to reliability and cost. The cracks grow in a mixed mode II & III, which in combination with the rotating stress field in the neighborhood of the crack-tip, large plastic deformations on the rail surface, crack face friction due to the compressive stresses from the wheel load and anisotropic crack growth resistance, add to the complexity related to the study of RCF cracks. LÄS MER