Sökning: "ab-initio"

Visar resultat 11 - 15 av 329 avhandlingar innehållade ordet ab-initio.

  1. 11. Theoretical and Experimental Studies of Electrode and Electrolyte Processes in Industrial Electrosynthesis

    Författare :Rasmus Karlsson; Ann Cornell; Jan Rossmeisl; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Electrocatalysis; metallic oxides; ruthenium dioxide; titanium dioxide; DSA; doping; selectivity; ab initio modeling; density functional theory; Elektrokatalys; metalloxider; ruteniumdioxid; titandioxid; DSA; dopning; selektivitet; ab initio-modellering; täthetsfunktionalteori; Chemical Engineering; Kemiteknik;

    Sammanfattning : Heterogeneous electrocatalysis is the usage of solid materials to decrease the amount of energy needed to produce chemicals using electricity. It is of core importance for modern life, as it enables production of chemicals, such as chlorine gas and sodium chlorate, needed for e.g. materials and pharmaceuticals production. LÄS MER

  2. 12. New Electrolyte Materials for Lithium Batteries and Fuel Cells - an ab initio and vibrational spectroscopy study

    Författare :Henrik Markusson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IR spectroscopy; lithium salts; Raman spectroscopy; ab initio calculations; electron structure calculations; protic ionic liquids; electrolytes;

    Sammanfattning : In order to reduce our fossil based energy consumption there is an urge for new energy storage and conversion devices such as lithium batteries and fuel cells for more efficient energy use. The heart of these devices is an ion conducting electrolyte which needs to provide high performance at low cost. LÄS MER

  3. 13. Insights into Materials Properties from Ab Initio Theory : Diffusion, Adsorption, Catalysis & Structure

    Författare :Andreas Blomqvist; Rajeev Ahuja; Christopher Wolverton; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Density functional theory; Molecular dynamics; Diffusion; Catalysis; Adsorption; Random structure search; Hydrogen-storage materials; Phase-change materials; Defects and diffusion; Defekter och diffusion; Surfaces and interfaces; Ytor och mellanytor; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this thesis, density functional theory (DFT) calculations and DFT based ab initio molecular dynamics simulations have been employed in order to gain insights into materials properties like diffusion, adsorption, catalysis, and structure. In transition metals, absorbed hydrogen atoms self-trap due to localization of metal d-electrons. LÄS MER

  4. 14. Ab initio Interlayer Potentials For Metals and Alloys

    Författare :Fuyang Tian; Levente Vitos; Nanxian Chen; Docent Kalevi Kokko; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mobius inversion; Potentials; EMTO; Järnvägsgruppen - Effektiva tågsystem för godstrafik; Järnvägsgruppen - Effektiva tågsystem för godstrafik; Järnvägsgruppen - Effektiva tågsystem för persontrafik; Järnvägsgruppen - Effektiva tågsystem för persontrafik;

    Sammanfattning : Many modern materials and material systems are layered. The properties related to layers are connected to interactions between atomic layers. In the present thesis, we introduce the interlayer potential (ILP), a novel model potential which fully describes the interaction between layers. LÄS MER

  5. 15. Electronic Structure and Core-Hole Dynamics of Ozone : Synchrotron-radiation based studies and ab-initio calculations

    Författare :Karoline Wiesner; Svante Svensson; Olle Björneholm; Robert E. Continetti; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik;

    Sammanfattning : The electronic structure of the ozone molecule O3 has been studied with spectroscopy techniques and computations. The investigation was focused on O3 in a core-hole state. The electronic configuration and the nuclear dynamics have been found to be highly correlated. LÄS MER