The formation of cosmic fullerenes from arophatic clusters
  Fullerenes have recently been identified in space and they may play a
significant role in the gas and dust budget of various astrophysical objects
including planetary nebulae (PNe), reflection nebulae (RNe) and H II regions.
The tenuous nature of the gas in these environments precludes the formation of
fullerene materials following known vaporization or combustion synthesis routes
even on astronomical timescales. We have studied the processing of hydrogenated
amorphous carbon (a-C:H or HAC) nano-particles and their specific derivative
structures, which we name "arophatics", in the circumstellar environments of
young, carbon-rich PNe. We find that UV-irradiation of such particles can
result in the formation of fullerenes, consistent with the known physical
conditions in PNe and with available timescales.
