Theoretical investigation of $\mathrm{FeSi_2}$ nanofilms and interface silicon/iron silicide

Electronic and geometric structure of $\beta$-phase of crystal $\mathrm{FeSi_2}$ is investigated by DFT calculations at different isotropic and axial pressures. It is revealed unusial increasing of the dielectric gap under the pressures. Also it is investigated electronic and geometric structure of $\mathrm{FeSi_2}$ nanofilms as well as silicon/iron silicide interface. It is defined that these nanofilms have surface reconstruction and corresponding conductivity. It is shown that contact of (001) silicon surface and corresponding surface of $\beta-\mathrm{FeSi_2}$ silicide lead to narrow perfeсt interface having conductivity near fermi level mainly due to contribution of the silicide surface layers.