Energy and photoinduced electron transfer in a wheel-shaped artificial photosynthetic antenna-reaction center complex
Artikel i vetenskaplig tidskrift, 2006

Functional mimics of a photosynthetic antenna-reaction center complex comprising five bis(phenylethynyl)anthracene antenna moieties and a porphyrin-fullerene dyad organized by a central hexaphenylbenzene core have been prepared and studied spectroscopically. The molecules successfully integrate singlet-singlet energy transfer and photoinduced electron transfer. Energy transfer from the five antennas to the porphyrin occurs on the picosecond time scale with a quantum yield of 1.0. Comparisons with model compounds and theory suggest that the Foster mechanism plays a major role in the extremely rapid energy transfer, which occurs at rates comparable to those seen in some photosynthetic antenna systems. A through-bond, electron exchange mechanism also contributes. The porphyrin first excited singlet state donates an electron to the attached fullerene to yield a P.+-C-60(.-) charge-separated state, which has a lifetime of several nanoseconds. The quantum yield of charge separation based on light absorbed by the antenna chromophores is 80% for the free base molecule and 96% for the zinc analogue.

Författare

G. Kodis

Y. Terazono

P. A. Liddell

Joakim Andreasson

Chalmers, Kemi- och bioteknik, Fysikalisk kemi

V. Garg

M. Hambourger

T. A. Moore

A. L. Moore

D. Gust

Journal of the American Chemical Society

Vol. 128 6 1818-1827

Ämneskategorier

Kemi