Amorphous silicon triboride: A first principles study


Ozlem A., Karacaoglan C., DURANDURDU M.

JOURNAL OF NON-CRYSTALLINE SOLIDS, vol.536, 2020 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 536
  • Publication Date: 2020
  • Doi Number: 10.1016/j.jnoncrysol.2020.119995
  • Title of Journal : JOURNAL OF NON-CRYSTALLINE SOLIDS

Abstract

Using ab initio molecular dynamics simulations, an amorphous silicon triboride (a-SiB3) network is generated and its atomic structure, electronic features and mechanical properties are compared with those of the crystal. The average coordination number of B and Si atoms in a-SiB3 is found as 5.8 and 4.6, correspondingly, close to 6.0 (B atom) and 5.0 (Si atom) in the crystal. A careful investigation reveals partial structural similarities around B atoms but not around Si atoms in both phases of SiB3. The presence of B-12, B11Si and B-10 molecules is witnessed in a-SiB3. The last two molecules, however, do not exist in the crystal. a-SiB3 is a semiconducting material. The bulk modulus of the ordered and disordered structures is projected to be 151 GPa and 131 GPa, respectively. The Vickers hardness of a-SiB3 is calculated to be similar to 13-15 GPa, less than similar to 20-25 GPa estimated for the crystal.