Sökning: "Margareta Blomberg"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Margareta Blomberg.

1. 1. Reactions, bonding and spectra of organometallic and diatomic molecules, studied by high accuracy quantum chemical methods

   Författare :Margareta Blomberg; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The main topic of the thesis is reductive elimination and oxidative addition reactions with nickel and palladium complexes. It is found that hydrogen is added to nickel much easier than both ethane and methane. LÄS MER

3. 2. Quantum chemical studies of epoxide-transforming enzymes

   Författare :Kathrin H. Hopmann; Hans Ågren; Margareta Blomberg; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Biokemi;

   Sammanfattning : Density functional theory is employed to study the reaction mechanisms of different epoxide-transforming enzymes. Calculations are based on quantum chemical active site models, which are build from X-ray crystal structures. The models are used to study conversion of various epoxides into their corresponding diols or substituted alcohols. LÄS MER

4. 3. Biomimetic Transition Metal Catalysts : Insights from Theoretical Modeling

   Författare :Adam Johannes Johansson; Per E. M. Siegbahn; Margareta R. A. Blomberg; Per-Ola Norrby; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Catalysis; biomimetic; copper; non-heme iron; heme iron; O2 cleavage; H-atom transfer; radical chemistry; redox chemistry; thermo chemistry; entropy calculations; quantum chemistry; spin states; density functional theory DFT ; self-interaction error SIE .; Chemical physics; Kemisk fysik; kemisk fysik; Chemical Physics;

   Sammanfattning : The scientific interest in the chemistry of synthetic transition metal complexes is motivated by at least two arguments:1.These can be regarded as models of biological transition metal complexes, e.g. metalloenzymes, whose functions can be difficult to reveal in detail due to their complexity. LÄS MER

5. 4. Challenges in Enzyme Catalysis - Photosystem II and Orotidine Decarboxylase : A Density Functional Theory Treatment

   Författare :Marcus Lundberg; Margareta Blomberg; Per Siegbahn; Jeremy Harvey; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photosystem II; oxyl radical; manganese systems; orotidine decarboxylase; reaction mechanism; density functional theory; Quantum chemistry; Kvantkemi;

   Sammanfattning : Possibly the most fascinating biochemical mechanism remaining to be solved is the formation of oxygen from water in photosystem II. This is a critical part of the photosynthetic reaction that makes solar energy accessible to living organisms. LÄS MER

7. 5. Biomimetic Iron Complexes involved in Oxygenation and Chlorination : A Theoretical Study

   Författare :Holger Noack; Margareta R. A. Blomberg; Per E. M. Siegbahn; Martin Kaupp; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; biomimetic; iron; density functional theory; intradiol; chlorination; adpic acid; diamond core; reactivity; Bio-inorganic chemistry; Bio-oorganisk kemi; Theoretical chemistry; Teoretisk kemi; kemisk fysik; Chemical Physics;

   Sammanfattning : Biomimetic chemistry is directed towards the simulation of enzymatic reactivity with synthetic analogues. In this thesis a quantum chemical method has been employed to study the mechanism of highly reactive iron-oxo complexes involved in oxygenation and chlorination of organic substrates. LÄS MER