Growth morphology of hexagonal crystal and the corresponding atomic density fields for the parts enclosed by dashed boxes, simulated with parameter n̄ = −0.47 at different times: (a) and (e) t = 2100, (b) and (f) t = 5000, (c) and (g) t = 19200, and (d) and (h) t = 72000. The white lines in panels (e) and (f) outline the newly generated layers. The color bar in the top row represents the variation of the smoothed atomic density field n_smooth.