Dependence of the thioxanthone triplet-triplet absorption spectrum with solvent polarity and aromatic ring substitution

Autor(es)

Giovana C. Ferreira ; Carla C. Schmitt ; Miguel G. Neumann

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 17, n. 5, p. 905-909, 2006-10-00.

Resumo

The triplet-triplet (TT) and transient absorptions of non-substituted and substituted thioxanthones has been studied in different solvents in order to ascertain the effect of the solvent, as well as the substituents on the aromatic ring. Spectra taken after a couple of ms after the flash show three main transient absorptions due to the triplet state (600-650 nm), the thioxanthone ketyl radical (~450 nm) and an overlap of both (~300 nm). The amount of radicals formed in non hydroxylic solvents is much lower than in alcohols. The maxima of the TT absorption peaks show a good correlation with the E T(30) solvent parameter. (AU)

• Processo FAPESP: 03/07770-4 - Interações de luz visível com polímeros: fotopolimerização e fotodegradação
• Beneficiário: MIGUEL GUILLERMO NEUMANN
• Modalidade de apoio: Auxílio à Pesquisa - Temático