Photophysical properties of non-homoconjugated 1,2-dihydro, 1,2,3,4-tetrahydro and 1,2,3,4,5,6-hexahydro-C60 derivatives.
The photophysical properties of a novel series of non-homoconjugated 1,2-di-, 1,2,3,4-tetra-, and 1,2,3,4,5,6-hexasubstituted fullerenes (compounds 1, 2, and 3, respectively) have been systematically investigated. In this report, we examine the effect of substitution pattern of non-homoconjugated derivatized fullerenes on the ground state UV-Vis absorption, triplet state properties (lifetime, quantum yield, extinction coefficient), and singlet oxygen quantum yield. The non-homoconjugated fullerene derivatives 1-3 exhibit higher singlet oxygen quantum yield than analogous homoconjugated Bingel adducts with the same number of saturated C[double bond, length as m-dash]C bonds and exhibit decreasing quantum yield of singlet oxygen generation upon increasing the degree of functionalization on a single six member ring on the fullerene cage. This trend is similar for triplet quantum yield and triplet lifetime. The triplet extinction coefficient increases with functionalization. A detailed discussion comparing 1, 2, and 3 with functionalized homoconjugated systems and with other non-homoconjugated derivatives is presented.
Chin
Khin K
KK
Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA.
Chuang
Shih-Ching
SC
Hernandez
Billy
B
Campos
Luis M
LM
Selke
Matthias
M
Foote
Christopher S
CS
Garcia-Garibay
Miguel A
MA