Sökning: "Charge-separated state"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Charge-separated state.

  1. 1. Controlling Charge and Energy Transfer Processes in Artificial Photosynthesis : From Picosecond to Millisecond Dynamics

    Författare :Magnus Borgström; Leif Hammarström; Jan Davidsson; Sebastiano Campagna; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Artificial photosynthesis; Electron transfer; Energy transfer; Ruthenium; Manganese; Charge-separated state; Donor-acceptor; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : This thesis describes an interdisciplinary project, where the aim is to mimic the initial reactions in photosynthesis. In photosynthesis, the absorption of light is followed by the formation of charge-separated states. The energy stored in these charge-separated states is further used for the oxidation of water and reduction of carbon dioxide. LÄS MER

  2. 2. The Fate of Electronically Excited States : Ultrafast Electron and Energy Transfer in Solvated Donor-Acceptor Systems

    Författare :Staffan Wallin; Leif Hammarström; Jan Davidsson; Eric Vauthey; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Electron transfer; Energy transfer; Anisotropy; Porphyrin; Ruthenium tris-bipyridine; Superexchange; Supramolecular; Donor-Acceptor; Charge transfer state; S2 state; Ultrafast; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

    Sammanfattning : Processes where a molecule absorbs visible light and then disposes of the excess energy via electron/energy transfer reactions have an important role both in nature (e.g. in photosynthesis) and in many technical applications (e.g. LÄS MER

  3. 3. Accumulative Charge Separation in Photocatalysis : From Molecules to Nanoparticles

    Författare :Mariia Pavliuk; Jacinto Sá; Leif Hammarström; Gary Brudvig; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Accumulative charge separation; Electron transfer; Plasmon dynamics; Time-resolved spectroscopy; Photocatalysis.; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

    Sammanfattning : Photochemical energy conversion into solar fuel involves steps of light absorption, charge separation and catalysis. Nature has taught us that the effective accumulation of redox equivalents and charge separation are the key steps in sunlight conversion. LÄS MER

  4. 4. Tuning electron transfer reactions by selective excitation in porphyrin-acceptor assemblies

    Författare :Mikael Andersson; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Physics; Fysik; Physics; Fysik; Physical Chemistry; fysikalisk kemi;

    Sammanfattning : This thesis concerns electron transfer reactions from different excited states in porphyrins, and the effect of changing the energy of the link connecting the donor and acceptor. Photoinduced electron transfer, and subsequent processes were studied using ultrashort laser pulses and nanosecond laser flash photolysis. LÄS MER

  5. 5. The Oxygen Evolving cycle in Photosystem II studied with EPR Spectroscopy at different pH and Temperature

    Författare :Susan F Morvaridi; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry; Naturvetenskap; Temperature; Natural science; pH; EPR; S cycle; Photosystem II;

    Sammanfattning : PSII catalyses the light-induced water splitting process which leads to electron transfer through the thylakoid membrane and formation of energy rich molecules. Several redox components including a Mn4Ca, an amino acid residueYZ, two special Chl molecules P680, two Pheo and two quinone molecules participate in this process. LÄS MER