Comprehensive study of nanodiamond and nanographite
formation from molten carbon with and without
the presence of hydrogen under varied conditions of external
pressure and cooling rate by Adler, A. Sorkin and R. Kalish.
Our success in nanodiamond formation
exceeded those of other good
computational groups and is in line with experiment;
possibly a result of our use of visualization techniques for their identification.
In the initial project (without hydrogen) our discovery of nanographite formation was a surprise.
Recently, nanoscale graphitic layers embedded in amorphous carbon were
We found that hydrogen-free nanodiamond crystals are precipitated more readily at
increased melt densities and cooling rates, whereas slower
cooling rates permit formation of graphitic layers.
In these visualizations we use different colors for
sp1, sp2 or sp3 hybridized carbon atoms. For example:
Red balls indicate sp3 bonded atoms, blue sp2, yellow sp, and large blue balls are hydrogen atoms.