Sökning: "Quantum chemical calculations"

Visar resultat 1 - 5 av 231 avhandlingar innehållade orden Quantum chemical calculations.

  1. 1. Quantum photoelectrochemistry : Theoretical studies of organic adsorbates on metal oxides surfaces

    Författare :Petter Persson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; Quantum chemistry; photoelectrochemistry; metal oxide surfaces; organic adsorbates; Kvantkemi; Quantum chemistry; Kvantkemi; Quantum Chemistry; kvantkemi;

    Sammanfattning : Interactions between organic molecules and transition metal oxide surfaces have been investigated by means of quantum chemical calculations. The studies have been aimed at understanding electrode-adsorbate interactions in photoelectrochemical devices, such as dye-sensitized solar cells. LÄS MER

  3. 2. Quantum Chemical Studies of Protein-Bound Chromophores, UV-Light Induced DNA Damages, and Lignin Formation

    Författare :Bo Durbeej; Leif Eriksson; Tim Clark; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; quantum chemistry; calculations; density functional theory; excited states; photochemistry; chromophores; absorption spectra; bathochromic shift; isomerization; UV radiation; DNA damages; cycloaddition reactions; photoenzymic repair; electron transfer; lignin; polymerization; phenoxy radicals; dilignols; Kvantkemi; Quantum chemistry; Kvantkemi;

    Sammanfattning : Quantum chemical methods have been used to provide a better understanding of the photochemistry of astaxanthin and phytochromobilin; the photoenzymic repair of UV-light induced DNA damages; and the formation of lignin. The carotenoid astaxanthin (AXT) is responsible for the colouration of lobster shell. LÄS MER

  4. 3. Modelling Chemical Reactions : Theoretical Investigations of Organic Rearrangement Reactions

    Författare :Per-Erik Larsson; Sten Lunell; Nessima Salhi-Benachenhou; Olle Matsson; Osvaldo Goscinski; Ian H. Williams; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; Kvantkemi; Quantum chemistry; Kvantkemi; Quantum Chemistry; Kvantkemi;

    Sammanfattning : Chemical reactions are ubiquitous and very important for life and many other processes taking place on earth. In both theoretical and experimental studies of reactivity a transition state is often used to rationalise the outcome of such studies. LÄS MER

  5. 4. Chloromethane Complexation by Cryptophanes : Host-Guest Chemistry Investigated by NMR and Quantum Chemical Calculations

    Författare :Zoltan Takacs; Jozef Kowalewski; Mikael Akke; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Host–guest complexes; inclusion phenomenon; cryptophanes; NMR; kinetics; activation energy; dipolar interaction; exchange; quantum chemical optimization; calculated chemical shifts; NOESY; cavity size; fysikalisk kemi; Physical Chemistry;

    Sammanfattning : Host–guest complexes are widely investigated because of their importance in many industrial applications. The investigation of their physico–chemical properties helps understanding the inclusion phenomenon. The hosts investigated in this work are cryptophane molecules possessing a hydrophobic cavity. LÄS MER

  7. 5. Quantum Chemical Interpretation of Protein Crystal Structure

    Författare :Kristina Nilsson; Beräkningskemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; structure; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi; protein; ComQum-X; Hess2FF; QM MM; hetero-compound; metal; oxidation state; protonation; force field; quantum refinement; refinement;

    Sammanfattning : An initial model in the crystallographic structure determination process, usually contains many errors. To produce an accurate model, one must carry out several cycles of crystallographic refinement. LÄS MER