PHOTOLUMINESCENCE STUDIES OF C-60 SINGLE-CRYSTALS

We present luminescence studies of solid C-60 for different morphologies such as C-60 films, polycrystalline C-60 powder, and C-60 single crystals. The number of spectrally resolvable peaks is highest for the single crystals as a consequence of reduced inhomogeneous broadening. The fluorescence spectrum of C-60 single crystals is composed of several defector surface-related C-60 emission centres. The fluorescence lines belonging to each of these so-called X-traps show the characteristic vibronic structure of molecular C-60 emission, i.e., they reflect the dominant T-1g-related false origins.