It was recalled that the soliton model for motion of the 90° partial in Si had provided an explanation for the large (1eV) reduction in activation energy which occurred under prolonged exposure to a H plasma. Application of the same model to diamond yielded a decrease of 1.6eV, and made dislocation motion possible again. The so-called atoms-in-molecules method was used here to examine the local energy minima and saddle-point structures which were involved in motion of the 90° partial. Bonds with graphite-like nature were found in the soliton solution and, to a greater extent, in the saddle points for motion and kink-pair nucleation. The presence of H did not suppress this nature in structures other than the kink pair, where H was far less compressed. The over-coordination of H in these structures was also characterized.
Quantitative Analysis of Bonding in 90° Partial Dislocation in Diamond. S.Jenkins, M.I.Heggie: Journal of Physics - Condensed Matter, 2000, 12, 10325-33