Figure 4. Transformation of hexagonal graphite with 0.208 nm interlayer distance into hexagonal diamond, in the figure the green and red balls represent atoms that have three and four nearest neighbors, respectively.

(a). The initial state of hexagonal graphite. (b). The configuration of hexagonal graphite after 10 ps relaxation. (c). Hexagonal graphite has slipped into orthorhombic graphite phase. (d). Parts of graphite convert into cubic diamond. (e). Graphite completely transforms into single-crystal hexagonal diamond. (f). The stress-strain curves in the compression process.