Ab initiostudies of structural and electronic properties of solid indium selenide under pressure

The solid phase of indium selenide is studied for pressures ranging from 0 to 8 GPa using several ab initio methods. The structural properties are explored within the density functional theory, and the electronic ones are completed by a more accurate quasiparticle approach. Both structural and electronic properties are compared to recent experimental data and show a very good agreement. In particular, the gaps obtained within the quasiparticle approach succeed in reproducing the direct to indirect gap transitions as the pressure is increased. Possible paths in the Brillouin zone for the indirect gap are proposed.