Sökning: "Charge transfer state"

Visar resultat 1 - 5 av 112 avhandlingar innehållade orden Charge transfer state.

  1. 1. 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

  2. 2. 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

  3. 3. Choreography of a proton pump : Studies of charge-transfer reactions in cytochrome c oxidase

    Författare :Jóhanna Vilhjálmsdóttir; Peter Brzezinski; Joachim Heberle; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; heme-copper oxidase; cytochrome c oxidase; respiration; proton pump; electron transfer; proton transfer; proton-transfer pathway; midpoint potential; proton-pumping mechanism; biokemi; Biochemistry;

    Sammanfattning : In the last step of cellular respiration, electrons from metabolites are transferred to molecular oxygen, mediated by the enzyme complexes of the respiratory chain. Some of these enzyme complexes couple these redox reactions to formation of an electrochemical proton gradient across the cell membrane. The proton gradient is used e.g. LÄS MER

  4. 4. Single and Accumulative Electron Transfer – Prerequisites for Artificial Photosynthesis

    Författare :Susanne Karlsson; Leif Hammarström; Hans-Christian Becker; Devens Gust; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Artificial photosynthesis; Photoinduced charge separation; Electron transfer; Energy transfer; Accumulative electon transfer; Donor-acceptor; Ruthenium; Linear arrays; Chemical physics; Kemisk fysik; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

    Sammanfattning : Photoinduced electron transfer is involved in a number of photochemical and photobiological processes. One example of this is photosynthesis, where the absorption of sunlight leads to the formation of charge-separated states by electron transfer. LÄS MER

  5. 5. Dynamics of Excitation Transfer and Charge Separation in Polymeric Semiconductors

    Författare :Arvydas Ruseckas; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Anisotropy; Photoinduced absorption; Femtosecond spectroscopy; Polythiophene; Conjugated polymers; Donor-Acceptor Complexes; Carbazole; Charge separation; Excitation transfer; Recombination; Physics; Fysik;

    Sammanfattning : Dynamics of optically excited electronic states have been studied in solid films and solutions of semiconducting polymers and model compounds. Transient absorption, monitored in the spectral range from 0.9 eV to 2.5 eV with a time resolution of about 100 fs, was the main experimental technique. LÄS MER