MODELING OF STRESS-INDUCED DIAMOND NUCLEATION

PM3 semi-empirical calculations have been used to model the primary di amond nucleation in the graphite-like initial carbon layer usually pro duced on substrates other than diamond. The effect of quenched-in dens ity increase was simulated by compressing the graphitic environment (r epresented by a small graphite cluster with cyclic boundary conditions ) of a carbon atom with an additional methyl group in its vicinity. Th e critical (linear) compression for the ''sp(2)-->sp(3) phase transfor mation'' of the fourfold coordinated carbon was estimated to be 3%.