Sökning: "Quantum Chemical Modeling"

Visar resultat 1 - 5 av 61 avhandlingar innehållade orden Quantum Chemical Modeling.

  1. 1. Quantum Chemical Modeling of Binuclear Zinc Enzymes

    Författare :Shilu Chen; Fahmi Himo; Luca De Gioia; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum Chemical Modeling; Binuclear; Zinc; Enzyme; DFT; Mechanism; Theoretical chemistry; Teoretisk kemi;

    Sammanfattning : In the present thesis, the reaction mechanisms of several di-zinc hydrolases have been explored using quantum chemical modeling of the enzyme active sites. The studied enzymes are phosphotriesterase (PTE), aminopeptidase from Aeromonas proteolytica (AAP), glyoxalase II (GlxII), and alkaline phosphatase (AP). LÄS MER

  3. 2. Quantum Chemical Cluster Modeling of Enzymatic Reactions

    Författare :Rongzhen Liao; Fahmi Himo; Robert Deeth; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cluster approach; density functional theory; B3LYP; enzyme; mechanism; dinuclear; trinuclear; zinc; tungsten; hydrolysis; decarboxylation; formaldehyde oxidation; hydration; methyl transfer; Quantum chemistry; Kvantkemi; organisk kemi; Organic Chemistry;

    Sammanfattning : The Quantum chemical cluster approach has been shown to be quite powerful and efficient in the modeling of enzyme active sites and reaction mechanisms. In this thesis, the reaction mechanisms of several enzymes have been investigated using the hybrid density functional B3LYP. LÄS MER

  4. 3. Photocatalysis for Indoor Air Cleaning : In situ FTIR and DFT Study of Acetaldehyde Photo-Oxidation on TiO2 and Sulfate-Modified TiO2

    Författare :Bozhidar Stefanov; Lars Österlund; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TiO2; acetaldehyde; crotonaldehyde; dimer; adsorption; DFT; FTIR; photocatalysis; micro-kinetic modeling; acid–base properties; surface functionalization; Solid State Physics; Fasta tillståndets fysik; Materialvetenskap; Materials Science;

    Sammanfattning : Acetaldehyde is among the group of VOC’s causing the so-called "sick building" syndrome. WHO has estimated that this problem, related to the indoor air-quality, affects one third of all buildings worldwide. TiO2 is an attractive material for the photocatalytic removal of VOC’s in the indoor environment. LÄS MER

  5. 4. Quantum Chemical Modeling of Dye-Sensitized Titanium Dioxide : Ruthenium Polypyridyl and Perylene Dyes, TiO2 Nanoparticles, and Their Interfaces

    Författare :Maria J. Lundqvist; Sten Lunell; Petter Persson; Lars Ojamäe; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; density functional theory; chromophore; nanocrystal; interface; photoexcitation; triplet state; surface electron transfer; electronic coupling strength; Kvantkemi; Quantum chemistry; Kvantkemi;

    Sammanfattning : Quantum chemical calculations have been used to model dye-sensitized nanostructured titanium dioxide systems that can be used in solar cells for solar energy to electricity conversion. Structural, electronic and spectral properties of isolated dyes and both bare and dye-sensitized TiO2 have been calculated with density functional theory, providing detailed information about both the separate parts and the dye-TiO2 interface. LÄS MER

  7. 5. Quantum Chemical Modeling of Asymmetric Enzymatic Reactions

    Författare :Maria E. S. Lind; Fahmi Professor; Rajeev Prabhakar; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biocatalysis; enantioselectivity; density functional theory; B3LYP; enzyme; hydrolysis; decarboxylation; Organic Chemistry; organisk kemi;

    Sammanfattning : Computational methods are very useful tools in the study of enzymatic reactions, as they can provide a detailed understanding of reaction mechanisms and the sources of various selectivities. In this thesis, density functional theory has been employed to examine four different enzymes of potential importance for biocatalytic applications. LÄS MER