Materials Data on MgSi2 by Materials Project

Abstract

MgSi2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Mg and ten Si atoms. Both Mg–Mg bond lengths are 3.00 Å. There are a spread of Mg–Si bond distances ranging from 2.75–2.91 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to two equivalent Mg and eight Si atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.15 Å. There are five inequivalent Si sites. In the first Si site, Si is bonded in a 11-coordinate geometry to five Mg and six Si atoms. There are a spread of Si–Si bond distances ranging from 2.69–2.75 Å. In the second Si site, Si is bonded in a 4-coordinate geometry to four equivalent Mg and four equivalent Si atoms. In the third Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms. There are one shorter (2.44 Å) and two longer (2.57 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded in a 9-coordinate geometry to four Mg and five Si atoms. The Si–Si bond length is 2.85 Å. In the fifth Si site, Si is bonded in a distorted square co-planar geometry to four equivalent Mg and six Si atoms.