Materials Data on MgSi by Materials Project
MgSi crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one MgSi sheet oriented in the (0, -1, 1) direction. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded in a 1-coordinate geometry to two Si atoms. There are one shorter (2.06 Å) and one longer (2.68 Å) Mg–Si bond lengths. In the second Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Si atoms. There are one shorter (2.80 Å) and one longer (2.85 Å) Mg–Si bond lengths. In the third Mg site, Mg is bonded in a 3-coordinate geometry to three Si atoms. There are a spread of Mg–Si bond distances ranging from 2.26–2.69 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 2-coordinate geometry to three Mg atoms. In the second Si site, Si is bonded in a distorted single-bond geometry to one Mg and two equivalent Si atoms. There are one shorter (2.22 Å) and one longer (2.37 Å) Si–Si bond lengths. In the third Si site, Si is bonded to three Mg and three Si atoms to form distorted edge-sharing SiMg3Si3 octahedra. The Si–Si bond length is 2.63 Å.