Materials Data on MgSi2 by Materials Project

Abstract

MgSi2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 6-coordinate geometry to nine Si atoms. There are a spread of Mg–Si bond distances ranging from 2.64–3.14 Å. In the second Mg site, Mg is bonded in a 1-coordinate geometry to eight Si atoms. There are a spread of Mg–Si bond distances ranging from 2.83–3.21 Å. In the third Mg site, Mg is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.75–3.03 Å. In the fourth Mg site, Mg is bonded in a 6-coordinate geometry to six Si atoms. There are a spread of Mg–Si bond distances ranging from 2.84–3.01 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded in a 8-coordinate geometry to four Mg and four Si atoms. There are a spread of Si–Si bond distances ranging from 2.39–2.53 Å. In the second Si site, Si is bonded in a 6-coordinate geometry to three Mg and three Si atoms. Both Si–Si bond lengths are 2.40 Å. In the third Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms. There are a spread of Si–Si bond distances ranging from 2.41–2.46 Å. In the fourth Si site, Si is bonded to three Mg and three Si atoms to form distorted edge-sharing SiMg3Si3 octahedra. There are two shorter (2.41 Å) and one longer (2.42 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 7-coordinate geometry to three Mg and four Si atoms. In the sixth Si site, Si is bonded in a 6-coordinate geometry to three equivalent Mg and three Si atoms. The Si–Si bond length is 2.39 Å. In the seventh Si site, Si is bonded in a 7-coordinate geometry to four Mg and three Si atoms. In the eighth Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms.