Not really a physics junkie, and I think this is a chemistry question, but since there's no chemistry.stackexchange.com (yet) I think here is the best place.
I was just reading up on nanotech and came across the phrase "can construct 0D fullerenes, 1D graphenes...". Flags went up at "0D fullerenes" and I can't find further information about it in many places.
A fullerene is apparently any pure-carbon atomic structure, in various forms, but the zero-dimensional part is throwing me. What is a 0D fullerene?