High-yield singlet fission in a zeaxanthin aggregate observed by picosecond resonance Raman spectroscopy.
We report high-yield triplet generation by singlet fission upon photoexcitation of a new aggregate of the carotenoid all-trans 3R,3'R-zeaxanthin. The yield is determined by picosecond time-resolved resonance Raman spectroscopy, which allows direct characterization and quantification of triplet excited-state signatures and ground-state depletion. The technique and analysis reveals that triplets form within picoseconds. A quantum yield of 90-200% is derived with the assumption of weak exciton-coupling in the zeaxanthin aggregate.
Wang
Chen
C
Department of Chemistry and Biochemistry, University of California-San Diego, 9500 Gilman Drive MC 0314, La Jolla, California 92093-0314, USA.
Tauber
Michael J
MJ