RT Journal Article
T1 Rigid dendritic donor-acceptor ensembles: Control over energy and electron transduction
A1 Guldi, Dirk
A1 Swartz, Angela
A1 Luo, Chuping
A1 Gómez Aspe, Rafael
A1 Segura Castedo, José Luis
A1 Martín León, Nazario
AB Several generations of phenylenevinylene dendrons, covalently attached to a C60 core, have been developed as synthetic model systems with hierarchical, fine-tuned architectures. End-capping of these dendritic spacers with dibutylaniline or dodecyloxynaphthalene, as antennas/electron donors, yielded new donor-bridge-acceptor ensembles in which one, two, or four donors are allocated at the peripheral positions of the well-defined dendrons, while the electron accepting fullerene is placed at the focal point of the dendron. On the basis of our cyclic voltammetry experiments, which disclose a single anodic oxidation and several cathodic reduction processes, we rule out significant, long-range couplings between the fullerene core and the end-standing donors in their ground-state configuration. Photophysical investigations, on the other hand, show that upon photoexcitation an efficient and rapid transfer of singlet excited-state energy (6 × 1010 to 2.5 × 1012 s-1) controls the reactivity of the initially excited antenna portion. Spectroscopic and kinetic evidence suggests that yet a second contribution, that is, an intramolecular electron-transfer, exists, affording C60.--dendron.+ with quantum yields (Φ) as high as 0.76 and lifetimes (τ) that are on the order of hundreds of nanoseconds (220-725 ns). Variation of the energy gap modulates the interplay of these two pathways (i.e., competition or sequence between energy and electron transfer).
PB American Chemical Society
YR 2002
FD 2002
LK https://hdl.handle.net/20.500.14352/105571
UL https://hdl.handle.net/20.500.14352/105571
LA eng
NO Dirk M. Guldi, Angela Swartz, Chuping Luo, Rafael Gómez, José L. Segura, and Nazario Martín Journal of the American Chemical Society 2002 124 (36), 10875-10886
NO DGESIC of Spain
DS Docta Complutense
RD 21 abr 2025