Excited state processes of upconverted emission of fullerene and related complex

Spectral studies of fullerene compound, C60, and fullerene–metal complex, C60[W(CO)3diphos], were performed. Upconverted emission was found in these two categories of specimens. Upconverted emission was attributed to the radiative transitions associated with the upper-lying excited singlet states. Introduction of the metal into the complex was found to have a significant effect on intersystem crossing. A simulation of and a data fitting to upconverted emission versus excitation intensity indicated that intersystem crossing changed to be 0.8 ps for the fullerene–metal complex in comparison to 7 ps for the C60 compound.