Liquid crystals and molecular architecture in studying intramolecular electron transfer in donor-acceptor systems
نویسنده
چکیده
We report the results of time-resolved electron paramagnetic resonance (TREPR) studies of photoinduced charge separation in different supramolecular donor-acceptor systems dissolved in oriented liquid crystals (LC). Three systems are discussed: 1) covalently linked donor-spacer-acceptor systems (DsA); 2) donor-acceptor systems linked by hydrogen bonds; and 3) a zwitterionic system in which the donor and acceptor parts are charged in their ground state. In all systems, selective photoexcitation of the donor part results in intramolecular electron transfer (IET) producing charge-separated states to form spin correlated or triplet radical pairs, i.e., SCRP and TRP, respectively, monitored by TREPR spectroscopy. It is the unique dielectric properties of the LCs that allow studying in details the electron transfer dynamics, the electron spin polarization (ESP), and the energetics of the charge separated states.
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