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dc.contributor.authorBespalova, Olena.en_US
dc.date.accessioned2009-07-14T19:41:01Z
dc.date.available2009-07-14T19:41:01Z
dc.date.issued2004-07-14T19:41:01Z
dc.identifier.urihttp://hdl.handle.net/10464/2279
dc.description.abstractThere is considerable interest in intramolecular energy transfer, especially in complexes which absorb visible light, because it is crucial to the better understanding of photoharvesting systems in photosynthetic organisms and for utilizing solar energy as well. Porphyrin dimers represent one of the best systems for the exploration of light-induced intramolecular energy transfer. Many kinds of porphyrins and porphyrin dimers have been studied over the past decade, however little attention has been paid to the influence of paramagnetic metals on the behavior of their excited states. In this thesis, Electron Paramagnetic Resonance Spectroscopy (EPR) is used to study such compounds. After light irradiation, porphyrins easily produce a variety of excited states, which are spin polarized and can be detected by the time-resolved (TR) EPR technique. The spin polarized results for vanadyl porphyrins, their electrostatically-coupled dimers, a covalently-linked copper porphyrin-free base porphyrin dimer, and free base porphyrins are presented in this thesis. From these results we can conclude that the spin polarization patterns of vanadyl porphyrins come primarily from the trip-quartet state generated by intersystem crossing (lSC) from the excited sing-doublet state through the trip-doublet state. The spin polarization pattern of electrostatically-coupled vanadyl porphyrin-free base porphyrin dimer is produced by the triplet state of the free base porphyrin half which is coupled to the unpaired electron on the vanadyl ion.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectPhotosynthesisen_US
dc.subjectPorphyrins.en_US
dc.subjectElectron paramagnetic resonance spectroscopy.en_US
dc.titleA time-resolved electron paramagnetic resonance spectroscopy study of paramagnetic porphyrins /en_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Chemistryen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Chemistryen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US
refterms.dateFOA2021-08-07T02:16:55Z


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