Figure 4: Void shape and vacancy inter-facet diffusion paths.
From: In-situ atomic-scale observation of irradiation-induced void formation
(a) Illustration of three-dimensional geometry and facet indexes of a void with small thickness bounded by {0001} and 
facets. (b) Geometry and facet indexes of a void with larger thickness bounded by {0001}, 
and 
facets. (c) Atomic configuration for vacancy diffusion paths between a (0001) facet and the 
facets (A-B-C or D-E-F-G) for a five-atomic-layer-thick void (N=5). The image is projected along a 
direction. Two possible different diffusion paths are considered due to the double lattice structure in hcp49.
