fig9

Figure 9. First-principles calculations of (A) isometric and front views of a Si-I crystal structure under a diamond indenter and (B) a deformed crystal structure under compression. Inset in (B) shows red and blue top views taken from an isometric view of deformed Si-I under compression. First-principles calculations of (C) a rotated crystal structure under shear stress from the red and blue top views shown in the inset of (B). (D) Variations of average energy and force of an atom as a function of angle during the rotation process shown in (C). Inset in (D) shows the formation of Si-VI from Si-I after compression and rotation under a diamond indenter. Figure reproduced from Ref.^[66] with permission from the Royal Society of Chemistry.