Search for dissertations about: "Proton-coupled electron transfer"

Showing result 1 - 5 of 17 swedish dissertations containing the words Proton-coupled electron transfer.

2. 1. Proton-Coupled Electron Transfer from Hydrogen-Bonded Phenols

   Author : Tania Irebo; Leif Hammarström; James M. Mayer; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Proton-coupled electron transfer; phenol oxidation; hydrogen bonds; artificial photosynthesis; promoting vibrations; proton transfer; laser flash-quench; transient absorption.; Physical chemistry; Fysikalisk kemi; Fysikalisk kemi; Physical Chemistry;

   Abstract : Proton-coupled electron transfer (PCET) is one of the elementary reactions occurring in many chemical and biological systems, such as photosystem II where the oxidation of tyrosine (TyrZ) is coupled to deprotonation of the phenolic proton. This reaction is here modelled by the oxidation of a phenol covalently linked to a Ru(bpy)32+-moitey, which is photo-oxidized by a laser flash-quench method. READ MORE

4. 2. Tailing Charges on New Paths : Ultrafast intramolecular charge transfer in chromophores

   Author : Belinda Pettersson Rimgard; Leif Hammarström; Oliver S. Wenger; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; intramolecular charge transfer; interligand electron transfer; electron transfer; proton transfer; concerted electron-proton transfer; Marcus inverted region; solvent; temperature; femtosecond spectroscopy; proton-coupled energy transfer; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

   Abstract : By tailing charges on their paths within a molecule, one can gain fundamental knowledge of their inherent reactivity. The charges, originally residing in their lowest energy configuration, can upon light absorption move across the system, or transfer in between them. READ MORE

5. 3. Regulation of Proton Coupled Electron Transfer from Amino Acids in Artificial Model Systems: A Mechanistic Study

   Author : Martin Sjödin; Leif Hammarström; Jan Davidsson; G. Daniel Nocera; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Proton Coupled Electron Transfer; Tyrosine; Tryptophan; Electron Transfer; Hydrogen bond; Photosystem II; Proton transfer; Radical protein; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Abstract : Amino acid radicals are key redox intermediates in several natural enzymes including Cytochrome c peroxidase, DNA photolyase, ribonucletide reductase, cytochrome c oxidase and photosystem II. Electron transfer from amino acids is often coupled to deprotonation and this thesis concerns the coupling of electron transfer from tyrosine and tryptophan to trisbipyridineruthenium(III) with deprotonation in model complexes. READ MORE

6. 4. Deciphering the Mechanistic Diversity of Proton-Coupled Electron Transfer Reactions

   Author : Robin Tyburski; Leif Hammarström; Thomas Moore; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; PCET; Proton Coupled Electron Transfer;

   Abstract : Proton coupled electron transfer is ubiquitous in biological and artificial reaction systems. Much has been done in order to describe the occurrence of such reactions. However, PCET reactivity is often very complex. For instance, there are multiple (stepwise and concerted) mechanistic pathways through which PCET may occur. READ MORE

7. 5. Mechanistic Studies on Proton-Coupled Electron Transfer from Tyrosine and Tryptophan Derivatives

   Author : Astrid Nilsen-Moe; Leif Hammarström; Pia Ädelroth; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Proton-Coupled Electron Transfer; PCET; Tyrosine; Tryptophan; Amino Acid Radicals; Transient Absorption; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

   Abstract : Proton-coupled electron transfer (PCET) from tyrosine (Y) and tryptophan (W) is vital to many redox reactions in Nature where PCET between several Ys, or Ws, or between a mix of Ys and Ws can be used to transfer electrons, or protons, or both over large distances of several Å. Studying the PCET reaction mechanisms of Y and W is important for fundamental knowledge, and can help researchers that wish to mimic redox reactions in Nature. READ MORE