High-efficiency energy transfer from carotenoids to a phthalocyanine in an artificial photosynthetic antenna.
Two carotenoid pigments have been linked as axial ligands to the central silicon atom of a phthalocyanine derivative, forming molecular triad 1. Laser flash studies on the femtosecond and picosecond time scales show that both the carotenoid S1 and S2 excited states act as donor states in 1, resulting in highly efficient singlet energy transfer from the carotenoids to the phthalocyanine. Triplet energy transfer in the opposite direction was also observed. In polar solvents efficient electron transfer from a carotenoid to the phthalocyanine excited singlet state yields a charge-separated state that recombines to the ground state of 1.
Department of Chemistry and Biochemistry and the Center for the Study of Early Events in Photosynthesis, Arizona State University, Tempe 85287-1604, USA.
Ernesto
E
Mariño-Ochoa
Rodrigo
R
Palacios
Gerdenis
G
Kodis
Alisdair N
AN
Macpherson
Tomas
T
Gillbro
Devens
D
Gust
Thomas A
TA
Moore
Ana L
AL
Moore