Photophysical properties of C-180 "cis-2/cis-2/cis-2", a triangle triad of
C-60, were investigated by various methods including a transient absorption
spectroscopy. Fluorescence and triplet absorption spectra were similar to
those of C-120 (C-60 dimer) and other 1,2-adducts of C-60. On the other han
d, short fluorescence lifetime and small quantum yield for the intersystem
crossing process indicate that the photophysical properties of C-180 are af
fected by the non-radiative process in the singlet excited state.