MgSi crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Mg(2), one Si(1), and three equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 14-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(1), one Si(3), four equivalent Si(1), and five equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Mg(2), one Si(2), two equivalent Si(1), and three equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to one Mg(1), two equivalent Mg(3), four equivalent Mg(2), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Mg(3), five equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Mg(2), three equivalent Mg(1), three equivalent Mg(3), and one Si(3) atom.
MgSi crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Mg(2), one Si(1), and three equivalent Si(3) atoms. There is one shorter (3.09 Å) and one longer (3.12 Å) Mg(1)-Mg(2) bond length. The Mg(1)-Si(1) bond length is 2.67 Å. There are a spread of Mg(1)-Si(3) bond distances ranging from 2.74-2.82 Å. In the second Mg site, Mg(2) is bonded in a 14-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(1), one Si(3), four equivalent Si(1), and five equivalent Si(2) atoms. The Mg(2)-Mg(2) bond length is 3.03 Å. The Mg(2)-Mg(3) bond length is 3.10 Å. The Mg(2)-Si(3) bond length is 2.84 Å. There are a spread of Mg(2)-Si(1) bond distances ranging from 2.97-3.03 Å. There are a spread of Mg(2)-Si(2) bond distances ranging from 2.95-3.17 Å. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Mg(2), one Si(2), two equivalent Si(1), and three equivalent Si(3) atoms. The Mg(3)-Si(2) bond length is 2.91 Å. There is one shorter (3.02 Å) and one longer (3.15 Å) Mg(3)-Si(1) bond length. There are a spread of Mg(3)-Si(3) bond distances ranging from 2.77-2.88 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to one Mg(1), two equivalent Mg(3), four equivalent Mg(2), and three equivalent Si(2) atoms. There are a spread of Si(1)-Si(2) bond distances ranging from 2.47-2.65 Å. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Mg(3), five equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. The Si(2)-Si(2) bond length is 2.54 Å. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Mg(2), three equivalent Mg(1), three equivalent Mg(3), and one Si(3) atom. The Si(3)-Si(3) bond length is 2.55 Å.