Sökning: "Anisotropic interactions"

Visar resultat 6 - 10 av 55 avhandlingar innehållade orden Anisotropic interactions.

  1. 6. Adsorbate Interactions and Growth Morphology

    Författare :Staffan Ovesson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The theory of growth has transformed substantially during the past decade. Whereas early theoretical methods were largely empirical, phenomenological, and continuum-based, today's tools include a quantitative, atomistic methodology on a first-principles basis. LÄS MER

  2. 7. Parametric Model for Astrophysical Proton-Proton Interactions and Applications

    Författare :Niklas Karlsson; Per Carlson; Simon Swordy; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; astrophysics; gamma rays; proton-proton interactions; cosmic rays; Astronomy and astrophysics; Astronomi och astrofysik;

    Sammanfattning : Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. LÄS MER

  3. 8. Van der Waals Interactions in Density Functional Theory

    Författare :Erika Hult; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; van der Waals interaction; exchange-correlation energy; adhesion; intermolecular forces; physisorption; density functional theory;

    Sammanfattning : Density functional theory is a very important method for calculating ground-state properties for atoms, molecules and solids. Albeit exact in principle, its implementation requires an approximation for the so-called exchange-correlation energy. LÄS MER

  4. 9. New solid-state NMR methods for exciting and separating anisotropic interactions of spin I=1 nuclei

    Författare :Rihards Aleksis; Andrew Pell; Robert Schurko; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solid-state NMR; quadrupolar; paramagnetic shifts; spinning solids; materials; Physical Chemistry; fysikalisk kemi;

    Sammanfattning : Solid-state NMR has become an essential tool for structural characterisation of materials, in particular systems with poor crystallinity and structural disorder. In recent years, a surge of interest has been observed for the study of paramagnetic systems, in which the interaction between nuclei and unpaired electrons allows to probe the electronic structure and properties of materials more directly. LÄS MER

  5. 10. Solitons, vortices and shell structure in ultracold atomic quantum systems

    Författare :Gunnar Eriksson; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; few-body physics; finite-size effects; solitary waves; quantized vortices; quantum hysteresis; shell structure; dipolar interactions; Fysicumarkivet A:2020:Eriksson;

    Sammanfattning : This dissertation deals with finite-size effects in a few different quantum many-body phenomena in ultracold atomic systems. The finite-sized systems were simulated numerically using both mean-field methods and methods beyond mean-field, e.g. quadratic configuration interaction and exact diagonalization. LÄS MER