Excited states quenching of phenosafranine dye by electron donors

The quenching of the excited singlet and triplet states of phenosafranine by aromatic amines, methoxybenzenes and triethanolamine was investigated in acetonitrile and methanol. The rate constants for the aromatic quenchers present a typical dependence of an electron transfer process with the one-ele...

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Detalhes bibliográficos
Autores: Broglia, Martin Federico, Bertolotti, Sonia Graciela, Previtali, Carlos Mario
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/115564
Acesso em linha:http://hdl.handle.net/11336/115564
Access Level:acceso abierto
Palavra-chave:DYES
ELECTRON TRANSFER
LASER FLASH PHOTOLYSIS
PHENOSAFRANINE
QUENCHING PROCESS
SEMIREDUCED DYE
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descrição
Resumo:The quenching of the excited singlet and triplet states of phenosafranine by aromatic amines, methoxybenzenes and triethanolamine was investigated in acetonitrile and methanol. The rate constants for the aromatic quenchers present a typical dependence of an electron transfer process with the one-electron redox potential of the donor. A Rehm-Weller correlation is obtained with the driving force. The fitting parameters are very similar in both solvents. The electron transfer nature of the quenching reaction is further confirmed by the detection of the radical cations of the quenchers and the semireduced form of the dye in laser flash photolysis experiments. The absorption coefficients of the transient species were estimated, and the quantum yield of the charge separation process was determined.