Sökning: "Conjugated bridges"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Conjugated bridges.

  1. 1. Bridge Mediated Electron Transfer in Conjugated and Cross-Conjugated Donor-Acceptor Compounds

    Författare :Erik Göransson; Leif Hammarström; Hans-Christian Becker; Michael R. Wasielewski; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Electron transfer; Ultrafast; Long-range; Intervalence charge transfer; cross conjugation; hyperconjugation; Physical Chemistry; Fysikalisk kemi;

    Sammanfattning : Detailed understanding of electron transfer reactions is important in many aspects of chemistry, biology and solar energy conversion.The main aim of this thesis is to provide further insight into electron transfer through highly conjugated bridge structures. LÄS MER

  2. 2. Energy and Electron Transfer in Porphyrin-Based Donor--Bridge--Acceptor Systems

    Författare :Kristine Kilså; Chalmers University of Technology; []
    Nyckelord :electron transfer; electronic coupling; donor--bridge--acceptor systems; quantum mechanical calculations; enhanced intersystem crossing; ligand and solvent effects; bridge mediation; energy transfer; porphyrin;

    Sammanfattning : The photophysical properties of supramolecular donor--bridge--acceptor systems have been investigated by spectroscopic and quantum mechanical methods. The systems consist of porphyrin donor and acceptor moieties linked by bridging chromophores of varying excitation energy, and are shown to be geometrically well-defined in terms of length and rotational conformation. LÄS MER

  3. 3. 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

  4. 4. Triplet Excitation Energy Transfer in Donor-Bridge-Acceptor Systems: Experimental and Theoretical Investigations

    Författare :Mattias P Eng; Chalmers University of Technology; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; self-assembled monolayer; density functional theory; triplet excitation energy transfer; gold porphyrin; electron transfer; spectroscopy; superexchange; electronic coupling;

    Sammanfattning : This thesis is a contribution to the understanding of bridge mediation of electron exchange processes in Donor-Bridge-Acceptor (D-B-A) systems. The field of research is relevant for the development and optimization of dye-sensitized solar cells, artificial photosynthesis, and the possible future development of molecular electronic devices. LÄS MER

  5. 5. Organic Heavy Group 14 Element Compounds : A Study of Their Chemical Bonding Properties Directed Towards Applications as Molecular Wires and in Synthesis

    Författare :Julius Tibbelin; Henrik Ottosson; Christoph Marschner; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Silicon; Group 14 Elements; Silenes; Conjugation; Chemical Bonding; Electronic Structure; Protecting Group Chemistry; Physical organic chemistry; Fysikalisk organisk kemi; Chemistry with specialization in Organic Chemistry; Kemi med inriktning mot organisk kemi;

    Sammanfattning : The research described herein includes synthesis, spectroscopy, and quantum chemical calculations with focus on the characteristic properties of compounds with bonds between carbon and the heavier Group 14 elements.The chapters based on the first four papers concern σ- and σ/π-conjugated compounds, although the focus of the first paper is on ring strain of bicyclo[1. LÄS MER