title: Geometric influence on intramolecular photoinduced electron transfer in platinum(II) acetylide-linked donor-acceptor assemblies.
abstract: A new donor-acceptor system, in which the electron donor triphenylamine (TPA) and the electron acceptor C60 are bridged through a cis- or trans-platinum(II) acetylide spacer have been prepared. Ground-state studies were conducted using electrochemistry and UV/Vis spectroscopy. Fluorescence studies suggested that charge transfer is the deactivation mechanism for the singlet excited state, and this was verified by transient absorption spectroscopy. Selective photoexcitation of 1 and 2 at 387 nm leads to a fast charge transfer between the TPA and C60, which gives rise to a radical ion-pair state (TPA(·+)-Pt-C60(·-)). Our results suggest that charge transfer is favored for the cis configuration while the presence of the trans configuration in the Pt(II) diacetylide results in a longer-lived charge separated states.
authors: Department of Chemistry, University of Texas at El Paso, 799618-0519 El Paso, Texas (USA).
authors: Agustín
authors: A
authors: Molina-Ontoria
authors: Danisha M
authors: DM
authors: Rivera-Nazario
authors: Alexis
authors: A
authors: Tigreros
authors: Alejandro
authors: A
authors: Ortiz
authors: José E
authors: JE
authors: Nuñez
authors: Braulio
authors: B
authors: Insuasty
authors: Daniela
authors: D
authors: Lueders
authors: Silke
authors: S
authors: Wolfrum
authors: Dirk M
authors: DM
authors: Guldi
authors: Luis
authors: L
authors: Echegoyen
keywords: electron transfer; excited states; fullerenes; platinum(II) acetylide; triphenylamine