Long Range Electron Transfer Quenching in Polyamine Chains Bearing a Terminal Naphthalene Unit

• Autor(a) principal: Pina, Fernando
• Data de Publicação: 2002
• Outros Autores: Lima, J. C., Lodeiro, Carlos, Melo, J. Seixas de, Díaz, Pilar, Teresa Albelda, M., García-España, Enrique
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/10413; https://doi.org/10.1021/jp025848j

The fluorescence emission of a naphthalene unit attached to a polyamine chain is quenched by intramolecular electron transfer from the deprotonated amines to the excited fluorophore. Measurements of the respective quenching rate constants as a function of the distance, reveal an exponential dependence with β = 0.45 Å-1. Identical measurements carried out in deuterated water have shown a similar dependence with the distance β = 0.49 Å-1 but an average reduction of the absolute values of the rate constants of ca. 1.2. The polyamine chains seem to constitute a bridge through which the electron can find a route to its movement, more efficiently than through space.