  We investigate effects of the local structure on the excitonic transport in
C60 thin films by means of temperature-dependent photoluminescence quenching
studies in a range of 5 to 300 K. Exciton motion in the X-ray amorphous layers
indicates thermally activated transport initiated above 80 K accompanied by a
thermalization of excitations into low lying states within the excitonic
density of states. Discontinuities in the temperature-dependent
photoluminescence behavior can be attributed to a continuous phase transition
at 80 K and a first order phase transition at 180 K, thereby revealing
structural information on the local film morphology in the C60 films.
