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 6-coordinate geometry to two equivalent Mg and nine Si atoms. There are one shorter (3.19 Å) and one longer (3.20 Å) Mg–Mg bond lengths. There are a spread of Mg–Si bond distances ranging from 2.91–3.33 Å. In the second Mg site, Mg is bonded in a 5-coordinate geometry to two equivalent Mg and seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.82–3.16 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded to three equivalent Mg and four Si atoms to form a mixture of distorted edge and corner-sharing SiMg3Si4 pentagonal bipyramids. There are a spread of Si–Si bond distances ranging from 2.36–2.48 Å. In the second Si site, Si is bonded in a 7-coordinate geometry to four Mg and three Si atoms. Both Si–Si bond lengths are 2.41 Å. In the third Si site, Si is bonded in a 8-coordinate geometry to four equivalent Mg and four Si atoms. The Si–Si bond length is 2.41 Å. In the fourth Si site, Si is bonded in a 7-coordinate geometry to five Mg and three Si atoms. The Si–Si bond length is 2.45 Å.