Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the monoclinic P2/c space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. There are two shorter (2.72 Å) and two longer (2.73 Å) Mg–Si bond lengths. In the second Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five equivalent Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.67–3.06 Å. In the third Mg2+ site, Mg2+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. All Mg–Si bond lengths are 2.73 Å. Si4- is bonded in a 9-coordinate geometry to nine Mg2+ atoms.