Photophysical properties of 2-nitro-5,10,15,20-tetra-p-tolylporphyrins.
Tetraarylporphyrins substituted with nitro groups at beta-pyrrolic positions are potential candidates for electron-accepting pigments in model systems for photosynthesis. The photophysics of 2-nitro-5,10,15,20-tetra-p-tolylporphyrin and its zinc analog have been studied in order to evaluate this potential. The ground state absorption spectrum, the triplet-triplet absorption spectrum, the fluorescence emission spectrum, and associated photophysical parameters have been determined. The molecules have short singlet lifetimes and anomalous temperature- and solvent-dependent emission spectra which are consistent with the formation of an intramolecular charge transfer state of the type P+.-NO2-. in which the nitro group is twisted about its bond to the porphyrin, relative to the ground state conformation.
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Department of Chemistry, Arizona State University, Tempe 85287-1604.
Moore
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Luttrull
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Seely
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Bittersmann
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Bensasson
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Rougée
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Land
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De Schryver
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Van der Auweraer
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D015394:Molecular Structure; D009574:Nitro Compounds / Q000138:chemical synthesis*; D011166:Porphyrins / Q000138:chemical synthesis*; D011838:Radiation-Sensitizing Agents / Q000138:chemical synthesis*; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D013329:Structure-Activity Relationship
D009574:Nitro Compounds; D011166:Porphyrins; D011838:Radiation-Sensitizing Agents