Atomistic study of ⅓〈 1 1 23〉{10 1 1} dislocations in h.c.p. crystals. I. Structure of the dislocation cores

The core structure of ⅓〈1 123〉 dislocations on {1011} planes in h.c.p. crystals has been studied by computer simulation using a truncated Lennard-Jones potential. An edge dislocation and a mixed dislocation parallel to the [2113] direction (30°dislocation) extend over the (1011) plane. A mixed dislocation parallel to the [1210] direction (105° dislocation) assumes either of the following three configurations, depending on initial elastic dislocations introduced: (i) a planar configuration spread over the (1011) plane, (ii) a nonplanar configuration spread over the (1011), (0001) and (1010) planes, (iii) another nonplanar configuration in which the disregistry is not confined to any low-index planes. The result is interpreted in terms of stacking faults in h.c.p. crystals.