Materials Data on MgSi2 by Materials Project

Abstract

MgSi2 is Magnesium tetraboride-like structured and crystallizes in the monoclinic Cm 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 two equivalent Mg and six Si atoms. Both Mg–Mg bond lengths are 3.13 Å. There are a spread of Mg–Si bond distances ranging from 2.69–2.80 Å. In the second 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 2.73–2.86 Å. In the third Mg site, Mg is bonded in a 8-coordinate geometry to two equivalent Mg and eight Si atoms. There are a spread of Mg–Si bond distances ranging from 2.80–3.05 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 2.78–2.94 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms. There are two shorter (2.40 Å) and one longer (2.45 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 6-coordinate geometry to three Mg and three Si atoms. There are two shorter (2.40 Å) and one longer (2.45 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 7-coordinate geometry to four Mg and three Si atoms. Both Si–Si bond lengths are 2.44 Å. In the fourth Si site, Si is bonded in a 7-coordinate geometry to three Mg and four Si atoms. There are two shorter (2.43 Å) and one longer (2.57 Å) Si–Si bond lengths. In the fifth Si site, Si is bonded in a 8-coordinate geometry to five Mg and three Si atoms. The Si–Si bond length is 2.63 Å. In the sixth Si site, Si is bonded in a 5-coordinate geometry to one Mg and four Si atoms. There are one shorter (2.52 Å) and one longer (2.64 Å) Si–Si bond lengths. In the seventh Si site, Si is bonded in a 7-coordinate geometry to three Mg and four Si atoms. In the eighth Si site, Si is bonded in a 7-coordinate geometry to three Mg and four Si atoms.