Sökning: "DFT-calculations"

Visar resultat 1 - 5 av 136 avhandlingar innehållade ordet DFT-calculations.

  1. 1. DFT calculations of initial localized corrosion of aluminum : Influence of aqueous ad-layer, chloride ions, and intermetallic particles

    Författare :Min Liu; Jinshan Pan; Ying Chen; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aluminum alloys; alumina; chloride; surface adsorption; aqueous ad-layer; localized corrosion; corrosion initiation; work function; micro-galvanic effect; density-functional theory; Volta potential; scanning kelvin probe force microscopy; Kemi; Chemistry;

    Sammanfattning : Localized corrosion of aluminum (Al, here including Al alloys) involves a series of physico-chemical processes at the interface between the metal and the aqueous ad-layer or the aqueous solution. The mechanisms that govern localized corrosion are quite complex and have been the subject of many experimental studies. LÄS MER

  3. 2. Lewis Acid Mediated Alkylation and Diels-Alder Reactions of 2H-Azirines

    Författare :Erik Risberg; KTH; []
    Nyckelord :2H-azirines; Lewis acid activation; chiral ligandsorganolithium reagentsDiels-Alder reactions; DFT-calculations;

    Sammanfattning : This thesis describes the use of 2H-azirines as reactivesubstrates in Lewis acid catalysed nucleophilic additions andin the Diels-Alder reaction.A number of carbon nucleophiles have been added to aseries of 2H-azirines in the presence and absence ofBF3·Et2O. LÄS MER

  4. 3. Asymmetric [2,3]-Sigmatropic Rearrangement of Allylic Ammonium Ylides

    Författare :Jan Blid; Peter Somfai; James C. Anderson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric; [2; 3]-sigmatropic rearrangement; allylic amine; ammonium ylide; Lewis acid; enantioselective; boron; phosphazene base; NMR spectroscopy; DFT-calculations; Organic chemistry; Organisk kemi;

    Sammanfattning : The thesis describes the realization of an asymmetric [2,3]-sigmatropic rearrangement of achiral allylic amines. It is divided into two parts; the first part deals with the development of a Lewis acid-mediated [2,3]-sigmatropic rearrangement and the second the asymmetric version thereof. LÄS MER

  5. 4. Catalysts for Oxygen Production and Utilization : Closing the Oxygen Cycle: From Biomimetic Oxidation to Artificial Photosynthesis

    Författare :Erik Karlsson; Jan-Erling Bäckvall; Björn Åkermark; Jerker Mårtensson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen; catalytic oxidation; biomimetic oxidation; artificial photosynthesis; water oxidation; DFT calculations; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis describes the development and study of catalysts for redox reactions, which either utilize oxygen or hydrogen peroxide for the purpose of selectively oxidizing organic substrates, or produce oxygen as the necessary byproduct in the production of hydrogen by artificial photosynthesis.The first chapter gives a general introduction about the use of environmentally friendly oxidants in the field of organic synthesis, and about the field of artificial photosynthesis. LÄS MER

  7. 5. Theoretical Investigations of C–O Activation in Biomass

    Författare :Pemikar Srifa; Joseph Samec; Supa Hannongbua; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DFT calculations; global minima hopping; reactive force field; lignin; palladium; nucleophilic substitution; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis focuses on using computational chemistry approaches to study how biobased molecules interact with both homo- and heterogeneous catalysts. The reaction mechanisms of such transformations have also been studied. LÄS MER