- Title
- Photophysicochemical and fluorescence quenching studies of tetra-and octa-carboxy substituted silicon and germanium phthalocyanines
- Creator
- Idowu, Mopelola, Nyokong, Tebello
- Subject
- To be catalogued
- Date
- 2009
- Type
- text
- Type
- article
- Identifier
- http://hdl.handle.net/10962/263500
- Identifier
- vital:53633
- Identifier
- xlink:href="https://doi.org/10.1016/j.jphotochem.2009.02.002"
- Description
- Spectral, photophysical and photochemical properties of tetra- and octa-carboxy substituted metallophthalocyanines containing silicon and germanium as central metals ((OH)2GeTCPc, (OH)2SiTCPc, (OH)2GeOCPc and (OH)2SiOCPc) have been studied in dimethylsulfoxide (DMSO) and the trends in triplet, fluorescence, singlet oxygen quantum yields and triplet lifetimes are described for these compounds. The GePc derivatives exhibited high triplet quantum yields (ΦT = 0.79 for (OH)2GeOCPc and 0.82 for (OH)2GeTCPc compared to ΦT = 0.66 for (OH)2SiTCPc and 0.48 for (OH)2SiOCPc) due to the spin–orbit coupling induced by Ge(IV). The triplet lifetimes were higher for MOCPc (τT = 760 μs for (OH)2SiOCPc and 480 μs for (OH)2GeOCPc compared to τT = 210 μs for (OH)2SiTCPc and 260 μs for (OH)2GeTCPc). The fluorescent states of the metallophthalocyanine (MPc) complexes were effectively quenched by benzoquinone (BQ) and the quenching course was found to follow a diffusion-controlled (dynamic) bimolecular mechanism. Theoretical values of bimolecular rate constant for the interaction of the complexes with BQ were determined using the Stokes–Einstein–Smoluchowski model, and values together with the Stern–Volmer quenching constants were used in calculating the fluorescence lifetimes of the complexes.
- Format
- computer, online resource, application/pdf, 1 online resource (6 pages), pdf
- Publisher
- Elsevier
- Language
- English
- Relation
- Journal of Photochemistry and Photobiology A: Chemistry, Idowu, M. and Nyokong, T., 2009. Photophysicochemical and fluorescence quenching studies of tetra-and octa-carboxy substituted silicon and germanium phthalocyanines. Journal of Photochemistry and Photobiology A: Chemistry, 204(1), pp.63-68, Journal of Photochemistry and Photobiology A: Chemistry volume 204 number 1 p. 63 2009 1010-6030
- Rights
- Publisher
- Rights
- Use of this resource is governed by the terms and conditions of the Elsevier Terms and Conditions Statement (https://www.elsevier.com/legal/elsevier-website-terms-and-conditions)
- Rights
- Closed Access
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Nyokong, Tebello (Distinguished Professor)
RU DST/NRF SARChI for Medicinal Chemistry and Nanotechnology
RU Department of Chemistry
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