Sökning: "Kvantkemi"

Visar resultat 26 - 30 av 63 avhandlingar innehållade ordet Kvantkemi.

1. 26. Reaction Mechanisms of Metalloenzymes and Synthetic Model Complexes Activating Dioxygen : A Computational study

   Författare :Valentin Georgiev; Per E.M. Siegbahn; Sam de Visser; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; catalysis; density functional theory; extradiol; intradiol; dioxygenases; oxygen; biomimetic complexes; heme; spin transition; adipic acid; Chemical physics; Kemisk fysik; kvantkemi; Quantum Chemistry;

   Sammanfattning : Quantum chemistry has nowadays become a powerful and efficient tool that can be successfully used for studies of biosystems. It is therefore possibleto model the enzyme active-site and the reactions undergoing into it, as well as obtaining quite accurate energetic profiles. LÄS MER

3. 27. Theoretical Reflections of Solvation in Polar Media

   Författare :Daniel Hagberg; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kvantkemi; Teoretisk kemi; quantum chemistry; Theoretical chemistry; Coordination; Water; Uranyl; Intermolecular forces; Simulation; Dielectric; Cluster; Hofmeister series; Ion; Interaction; Dipole;

   Sammanfattning : Using experiments it is rather easy to measure things on the macroscopic length scale, while it is much harder to measure something in the microscopic world like molecular structure. The opposite is true in theoretical chemistry. LÄS MER

4. 28. Structure and spectroscopy of bio- and nano-materials from first-principles simulations

   Författare :Weijie Hua; Yi LUO; Mauro Stener; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; soft x-ray spectroscopy; bio- and nano-materials; first-principles simulation; host-guest interaction; generalized energy-based fragmentation; Quantum chemistry; Kvantkemi; Spectroscopy; Spektroskopi; SRA - Molecular Bioscience; SRA - Molekylär biovetenskap;

   Sammanfattning : This thesis is devoted to first-principles simulations of bio- and nano-materials,focusing on various soft x-ray spectra, ground-state energies and structures of isolated largemolecules, bulk materials, and small molecules in ambient solutions. K-edge near-edge x-ray absorption fine structure (NEXAFS) spectra, x-ray emission spectra, andresonant inelastic x-ray scattering spectra of DNA duplexes have been studied by means oftheoretical calculations at the density functional theory level. LÄS MER

5. 29. Theoretical aspects of tetrapyrrole biochemistry

   Författare :Kasper Jensen; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Proteiner; enzymologi; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi; enzymology; Proteins; protein; enzyme; density functional; Heme; B12;

   Sammanfattning : Modern theoretical simulations are able to provide significant insight into biochemical problems on a scale which continues to expand. With the aid of computer power and the sophisticated programs of researchers in the field, we have addressed a series of problems related to the so-called tetrapyrrole cofactors found in all living organisms. LÄS MER

7. 30. Quantum chemical studies of catalytic N₂O decomposition and NOx storage on metal oxides

   Författare :Elly Johanne Karlsen; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kvantkemi;

   Sammanfattning : .... LÄS MER