Materials Data on Mg6SiGe2 by Materials Project

Abstract

Mg6Ge2Si crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to two equivalent Ge and two equivalent Si atoms to form a mixture of edge and corner-sharing MgSi2Ge2 tetrahedra. Both Mg–Ge bond lengths are 2.77 Å. Both Mg–Si bond lengths are 2.77 Å. In the second Mg site, Mg is bonded to three equivalent Ge and one Si atom to form a mixture of edge and corner-sharing MgSiGe3 tetrahedra. There are one shorter (2.77 Å) and two longer (2.78 Å) Mg–Ge bond lengths. The Mg–Si bond length is 2.77 Å. Ge is bonded in a body-centered cubic geometry to eight Mg atoms. Si is bonded in a body-centered cubic geometry to eight Mg atoms.