Materials Data on MgSi2 by Materials Project

Abstract

MgSi2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 9-coordinate geometry to two equivalent Mg and nine Si atoms. Both Mg–Mg bond lengths are 3.04 Å. There are a spread of Mg–Si bond distances ranging from 2.67–3.00 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to three Mg and nine Si atoms. The Mg–Mg bond length is 2.90 Å. There are a spread of Mg–Si bond distances ranging from 2.79–3.16 Å. There are five inequivalent Si sites. In the first Si site, Si is bonded in a 8-coordinate geometry to six Mg and four equivalent Si atoms. All Si–Si bond lengths are 2.54 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to five Mg and four Si atoms. There are two shorter (2.59 Å) and two longer (2.73 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 8-coordinate geometry to four Mg and four Si atoms. Both Si–Si bond lengths are 2.53 Å. In the fourth Si site, Si is bonded in a 8-coordinate geometry to three Mg and five Si atoms. The Si–Si bond length is 2.62 Å. In the fifth Si site, Si is bonded in a distorted q6 geometry to six Mg and four equivalent Si atoms.