First-principles predictions on transition from tetrahedron to octahedron, electronic structures and elastic properties of InAs

In this work, the pressure induced phase transition of InAs is investigated by density functional theory. The first-order phase transition of InAs from zinc-blende (ZB) to the rocksalt (RS) structure occurs at 4.9 GPa accompanies by a 26% volume collapse. It is found that the nearest In and As atoms bonded as covalent bond, but there is no strong interaction between the nearest In–In or As–As atoms. Crystal space of ZB structure is occupied by tetrahedrons (4 In–As covalent bonds) partly with many interstice, and crystal space of RS is fulfilled by close-packed octahedrons (6 In–As covalent bonds). With increasing pressure, rebuild of covalent bond due to variations of electronic structure causes phase transition from ZB to RS structure. Furthermore, directional changes of covalent bond along [100] and [110] bring evident variation of shear on the {100} and {110} planes.

► Phase transition of InAs from ZB to the RS structure occurs at 4.9 GPa.
► Fact of phase transition is the transition from tetrahedron to octahedron.
► Direction of covalent bonds would greatly affect the elastic properties of InAs.