Mg2Si3 is Magnesium tetraboride-like structured and crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to one Si(1), one Si(2), two equivalent Si(3), and two equivalent Si(6) atoms. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Si(6), four equivalent Si(1), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to one Si(4), one Si(5), two equivalent Si(3), and two equivalent Si(6) atoms. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to two equivalent Si(3), four equivalent Si(4), and four equivalent Si(5) atoms. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(6), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), one Si(5), and one Si(6) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(4), and three equivalent Si(5) atoms. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(3), and three equivalent Si(4) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Si(2), and one Si(3) atom.
Mg2Si3 is Magnesium tetraboride-like structured and crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to one Si(1), one Si(2), two equivalent Si(3), and two equivalent Si(6) atoms. The Mg(1)-Si(1) bond length is 2.90 Å. The Mg(1)-Si(2) bond length is 2.94 Å. There is one shorter (2.81 Å) and one longer (3.01 Å) Mg(1)-Si(3) bond length. There is one shorter (2.72 Å) and one longer (2.87 Å) Mg(1)-Si(6) bond length. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Si(6), four equivalent Si(1), and four equivalent Si(2) atoms. There is one shorter (2.85 Å) and one longer (2.86 Å) Mg(2)-Si(6) bond length. There are a spread of Mg(2)-Si(1) bond distances ranging from 3.02-3.13 Å. There are a spread of Mg(2)-Si(2) bond distances ranging from 2.81-3.13 Å. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to one Si(4), one Si(5), two equivalent Si(3), and two equivalent Si(6) atoms. The Mg(3)-Si(4) bond length is 2.92 Å. The Mg(3)-Si(5) bond length is 2.94 Å. There is one shorter (2.73 Å) and one longer (2.87 Å) Mg(3)-Si(3) bond length. There is one shorter (2.81 Å) and one longer (3.02 Å) Mg(3)-Si(6) bond length. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to two equivalent Si(3), four equivalent Si(4), and four equivalent Si(5) atoms. There is one shorter (2.85 Å) and one longer (2.86 Å) Mg(4)-Si(3) bond length. There are a spread of Mg(4)-Si(4) bond distances ranging from 3.01-3.15 Å. There are a spread of Mg(4)-Si(5) bond distances ranging from 2.80-3.14 Å. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. The Si(1)-Si(1) bond length is 2.44 Å. There are a spread of Si(1)-Si(2) bond distances ranging from 2.44-2.54 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(6), and three equivalent Si(1) atoms. The Si(2)-Si(6) bond length is 2.40 Å. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), one Si(5), and one Si(6) atom. The Si(3)-Si(5) bond length is 2.40 Å. The Si(3)-Si(6) bond length is 2.43 Å. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(4), and three equivalent Si(5) atoms. The Si(4)-Si(4) bond length is 2.45 Å. There are a spread of Si(4)-Si(5) bond distances ranging from 2.46-2.53 Å. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(3), and three equivalent Si(4) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Si(2), and one Si(3) atom.