Undissociated, metastable dislocations were observed in various crystals in addition to stable dissociated dislocations by high-resolution transmission electron microscopy. The origin of the metastablity of the undissociated state was discussed specifically for the dissociation into Shockley partial dislocations in face-centred cubic or hexagonal close-packed lattice. It was shown that the metastability was due either to a high Peierls–Nabarro stress larger than a few percent of the shear modulus of the partial dislocations and/or to the increase of the total core energy by an increase of the dangling bonds. The metastablity of undissociated dislocations in zincblende III–V compounds was concluded to be due to a contribution of the latter effect.

Metastablity of the Undissociated State of Dissociated Dislocations. S.Takeuchi: Materials Science and Engineering A, 2005, 400-401, 84-8