Sökning: "ab initio molecular dynamics"

Visar resultat 21 - 25 av 95 avhandlingar innehållade orden ab initio molecular dynamics.

  1. 21. Theoretical Description of the Electron-Lattice Interaction in Molecular and Magnetic Crystals

    Författare :Elham Mozafari; Igor A. Abrikosov; Sven Stafström; George Malcolm Stocks; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Molecular crystals; Charge transport; Polaron; Magnetic materials; Paramagnetic state; Molecular dynamics;

    Sammanfattning : Electron-lattice interactions are often considered not to play a major role in material's properties as they are assumed to be small, the second-order effects. However, this study shows the importance of taking these effects into account in the simulations. LÄS MER

  2. 22. Classical and Car-Parrinello Molecular Dynamics Simulations of Polyvalent Metal Ions in Water

    Författare :Sami Amira; Kersti Hermansson; Imre Bako; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; Car-Parrinello molecular dynamics simulations; ab initio calculations; ion; copper; aluminium; metal ion; water; aqueous solution; solvation; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi;

    Sammanfattning : The aqueous solvation of metal ions is one of the long-standing and complex problems in chemistry, with implications for and applications in a broad range of biochemical and electrochemical systems, where water is the all-pervasive medium.This thesis describes computer simulations of Al3+(aq), Fe2+(aq), Fe3+(aq) and Cu2+(aq). LÄS MER

  3. 23. Structure, dynamics and reactivity of low-oxidation state iron complexes in solution studied by ab initio molecular dynamics simulations and advanced quantum chemistry calculations

    Författare :Michael R. Coates; Michael Odelius; Bo Durbeej; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kemisk fysik; Chemical Physics;

    Sammanfattning : Third row (3d) metals, such as iron have become a candidate for a broad class of photocatalysts that have a large abundance on Earth and a low toxicity to humans and the environment. Unlike many commonly used photocatalysts that contain expensive precious metals, iron is cheap. LÄS MER

  4. 24. Multiscale Modeling of Molecular Sieving in LTA-type Zeolites : From the Quantum Level to the Macroscopic

    Författare :Amber Mace; Laaksonen Aatto; Tina Düren; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CO2 separation; carbon capture; kinetic sieving; Zeolite A; Zeolite NaKA; cation exchange; temporal coarse graining; Kinetic Monte Carlo; Molecular Dynamics; AIMD; DFT; fysikalisk kemi; Physical Chemistry;

    Sammanfattning : LTA-type zeolites with narrow window apertures coinciding with the approximate size of small gaseous molecules such as CO2 and N2 are interesting candidates for adsorbents with swing adsorption technologies due to their molecular sieving capabilities and otherwise attractive properties. These sieving capabilities are dependent on the energy barriers of diffusion between the zeolite pores, which can be fine-tuned by altering the framework composition. LÄS MER

  5. 25. Structure and Dynamics of Core-Excited Species

    Författare :Oksana Travnikova; Maria Novella Piancastelli; Svante Svensson; Denis Ceolin; Pascal Lablanqui; Uppsala universitet; []
    Nyckelord :Physics; Synchrotron radiation; X-ray Photoelectron Spectroscopy XPS ; X-ray Absorption Spectroscopy XAS ; Resonant Auger Spectroscopy RAS ; Auger Electron Spectroscopy AES ; Energy-Selected Auger Electron PhotoIon COincidence ES-AEPICO ; core excitation; core ionization; linear free energy relationships LFER ; molecular-field splitting; substituent effects; nuclear dynamics; isomerization; Cl2; N2O; methane derivatives; allene; acetylacetone; Fysik;

    Sammanfattning : In this thesis we have performed core-electron spectroscopy studies of gas phase molecular systems starting with smaller diatomic, continuing with triatomic and extending our research to more complex polyatomic ones. We can subdivide the results presented here into two categories: the first one focusing on electronic fine structure and effect of the chemical bonds on molecular core-levels and the other one dealing with nuclear dynamics induced by creation of a core hole. LÄS MER