A new form solid carbon has been synthesized consisting of a hexagonal close packing of C-26 molecules under energetic C-2(+) ion 2.4 MeV bombardment of ultra high molecular weight polyethylene. The beam current was about 150 mA and the total dose was 1 x 10(16) ions cm(-2). The residual gas pressure in the irradiation chamber was 1.3 x 10(-4) Pa during bombardment. High-resolution transmission electron microscopy, electron diffraction, and time-of-flight mass spectroscopy studies of the molecular packing confirm that the C-26 molecules have the caged fullerene structure
