Dislocation-Dissociation and SFE in Strontium Titanate

The inverse BDT for SrTiOs deformed along (100) or (110) is thought to be due to transformation of the dislocation core structure ]121] Gumbsch et al. [121] suggested a possible climb dissociation (more properly a decomposition) via the reaction 

However, the (100) product dislocations in Eq. (16) are both perfect dislocations and are perpendicular to one another. Frank s rule indicates that, to first order, such a reaction would not lead to reduction in the dislocation line energy, whether it occurs by glide or climb. Of course, if the screw/edge character of the (110) dislocation is taken into account, then Eq. (16) will be favorable for an edge dislocation and unfavorable for a screw dislocation. 

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