On the quenching of MLCT luminescence by amines: The effect of nanoaggregation in the decrease of the reorganization energy

LARISA L. B. BRACCO; MARIO R. FÉLIZ; EZEQUIEL WOLCAN

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY

ELSEVIER SCIENCE SA

Lugar: Londres; Año: 2010 vol. 210 p. 23 - 30

1010-6030

The MLCT luminescence quenching of pyRe(CO)3bpy+ and/or the polymer {[(vpy)2-vpyRe(CO)3bpy] CF3SO3}n–200 by amines proceeds via an electron transfer reaction which produces amine radical cations and pyReI(CO)3(bpy)•/–ReI(CO)3(bpy)•, respectively. The quenching follows a typical Stern–Volmer kinetics for both pyRe(CO)3bpy+ and {[(vpy)2-vpyRe(CO)3bpy]CF3SO3}n–200. The observed rate constants for the quenching of the ReI-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.3bpy+ and/or the polymer {[(vpy)2-vpyRe(CO)3bpy] CF3SO3}n–200 by amines proceeds via an electron transfer reaction which produces amine radical cations and pyReI(CO)3(bpy)•/–ReI(CO)3(bpy)•, respectively. The quenching follows a typical Stern–Volmer kinetics for both pyRe(CO)3bpy+ and {[(vpy)2-vpyRe(CO)3bpy]CF3SO3}n–200. The observed rate constants for the quenching of the ReI-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.3SO3}n–200 by amines proceeds via an electron transfer reaction which produces amine radical cations and pyReI(CO)3(bpy)•/–ReI(CO)3(bpy)•, respectively. The quenching follows a typical Stern–Volmer kinetics for both pyRe(CO)3bpy+ and {[(vpy)2-vpyRe(CO)3bpy]CF3SO3}n–200. The observed rate constants for the quenching of the ReI-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.I(CO)3(bpy)•/–ReI(CO)3(bpy)•, respectively. The quenching follows a typical Stern–Volmer kinetics for both pyRe(CO)3bpy+ and {[(vpy)2-vpyRe(CO)3bpy]CF3SO3}n–200. The observed rate constants for the quenching of the ReI-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.3bpy+ and {[(vpy)2-vpyRe(CO)3bpy]CF3SO3}n–200. The observed rate constants for the quenching of the ReI-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.I-polymer luminescence by amines show “vestiges” of the inverted effect predicted by Marcus while the quenching of pyRe(CO)3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.3bpy+ luminescence follow the Rehm–Weller type of behavior. The lower value obtained for the total reorganization energy of the ReI-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.I-polymer than that for pyRe(CO)3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.3bpy+ is rationalized in terms of the retarded solvent motions inside the nanoaggregates formed by the ReI-polymer in acetonitrile solutions.I-polymer in acetonitrile solutions. ©