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Materials Data on Mg2Si by Materials Project

Mg2Si is Fluorite structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. All Mg–Si bond lengths are 2.76 Å. Si4- is bonded in a body-centered cubic geometry to eight equivalent Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. All Mg–Si bond lengths are 3.28 Å. Si4- is bonded in a 12-coordinate geometry to twelve equivalent Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to five equivalent Si4- atoms to form MgSi5 trigonal bipyramids that share corners with twelve equivalent MgSi6 octahedra, corners with eight equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi5 trigonal bipyramids, and faces with six equivalent MgSi6 octahedra. The corner-sharing octahedra tilt angles range from 30–60°. There are three shorter (2.67 Å) and two longer (3.04 Å) Mg–Si bond lengths. In the second Mg2+ site, Mg2+ is bonded to six equivalent Si4- atoms to form MgSi6 octahedra that share corners with twelve equivalent MgSi6 octahedra, corners with twelve equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi6 octahedra, faces with two equivalent MgSi6 octahedra, and faces with six equivalent MgSi5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. All Mg–Si bond lengths are 3.08 Å. Si4- is bonded in a 11-coordinate geometry to eleven Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–2.77 Å. In the second Mg2+ site, Mg2+ is bonded to four Si4- atoms to form a mixture of edge and corner-sharing MgSi4 trigonal pyramids. There are a spread of Mg–Si bond distances ranging from 2.87–3.06 Å. In the third Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.80–2.87 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–2.82 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 8-coordinate geometry to seven Mg2+ and one Si4- atom. The Si–Si bond length is 2.51 Å. In the second Si4- site, Si4- is bonded in a 8-coordinate geometry to seven Mg2+ and one Si4- atom.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to five Si4- atoms to form a mixture of distorted corner and edge-sharing MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.74–2.92 Å. In the second Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.75–3.25 Å. In the third Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.23 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.75–3.25 Å. In the fifth Mg2+ site, Mg2+ is bonded to five Si4- atoms to form a mixture of distorted corner and edge-sharing MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.74–2.92 Å. In the sixth Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.81–3.08 Å. In the seventh Mg2+ site, Mg2+ is bonded in a linear geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.30 Å. In the eighth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.24 Å. There are four inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 11-coordinate geometry to ten Mg2+ and one Si4- atom. The Si–Si bond length is 2.57 Å. In the second Si4- site, Si4- is bonded in a 11-coordinate geometry to ten Mg2+ and one Si4- atom. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to nine Mg2+ atoms. In the fourth Si4- site, Si4- is bonded in a 9-coordinate geometry to nine Mg2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.15 Å. In the second Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.18 Å. In the third Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.72–3.11 Å. In the fourth Mg2+ site, Mg2+ is bonded to four Si4- atoms to form distorted edge-sharing MgSi4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.71–2.87 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. The Si–Si bond length is 2.41 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. The Si–Si bond length is 2.48 Å.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to five equivalent Si4- atoms to form MgSi5 trigonal bipyramids that share corners with twelve equivalent MgSi6 octahedra, corners with eight equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi5 trigonal bipyramids, and faces with six equivalent MgSi6 octahedra. The corner-sharing octahedra tilt angles range from 27–61°. There are a spread of Mg–Si bond distances ranging from 2.66–3.12 Å. In the second Mg2+ site, Mg2+ is bonded to six equivalent Si4- atoms to form distorted MgSi6 octahedra that share corners with twelve equivalent MgSi6 octahedra, corners with twelve equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi6 octahedra, faces with two equivalent MgSi6 octahedra, and faces with six equivalent MgSi5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Mg–Si bond distances ranging from 2.98–3.17 Å. Si4- is bonded in a 3-coordinate geometry to eleven Mg2+ atoms.

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Materials Data on Li(Mg2Si)2 by Materials Project

Li(Mg2Si)2 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Li is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. All Li–Mg bond lengths are 2.84 Å. Mg is bonded in a 6-coordinate geometry to two equivalent Li and four Si atoms. There are two shorter (2.77 Å) and two longer (2.84 Å) Mg–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. In the second Si site, Si is bonded in a body-centered cubic geometry to eight equivalent Mg atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.84–3.20 Å. In the second Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.93–3.08 Å. In the third Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.94–3.06 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.82–3.20 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to ten Mg2+ atoms. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to ten Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si is Cotunnite structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four equivalent Si4- atoms to form a mixture of distorted corner and edge-sharing MgSi4 trigonal pyramids. There are a spread of Mg–Si bond distances ranging from 2.63–2.87 Å. In the second Mg2+ site, Mg2+ is bonded in a distorted see-saw-like geometry to four equivalent Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–2.90 Å. Si4- is bonded in a 8-coordinate geometry to eight Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.79–2.99 Å. In the second Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.03 Å. In the third Mg2+ site, Mg2+ is bonded in a distorted T-shaped geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.89–2.98 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–3.14 Å. In the fifth Mg2+ site, Mg2+ is bonded in a distorted L-shaped geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.80–3.31 Å. In the sixth Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.76–2.95 Å. In the seventh Mg2+ site, Mg2+ is bonded in a distorted water-like geometry to two Si4- atoms. There are one shorter (2.73 Å) and one longer (2.79 Å) Mg–Si bond lengths. In the eighth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.72–3.06 Å. There are four inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to six Mg2+ and two Si4- atoms. There are one shorter (2.54 Å) and one longer (2.60 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to seven Mg2+ and two Si4- atoms. The Si–Si bond length is 2.64 Å. In the third Si4- site, Si4- is bonded in a 10-coordinate geometry to eight Mg2+ and two Si4- atoms. The Si–Si bond length is 2.87 Å. In the fourth Si4- site, Si4- is bonded in a 5-coordinate geometry to five Mg2+ and two Si4- atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.66–2.91 Å. In the second Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.03 Å. In the third Mg2+ site, Mg2+ is bonded to four Si4- atoms to form a mixture of distorted edge and corner-sharing MgSi4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.72–2.83 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.83–3.13 Å. In the fifth Mg2+ site, Mg2+ is bonded in a distorted water-like geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.77–3.21 Å. In the sixth Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.86–3.05 Å. In the seventh Mg2+ site, Mg2+ is bonded in a distorted T-shaped geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.64–3.03 Å. In the eighth Mg2+ site, Mg2+ is bonded to four Si4- atoms to form a mixture of distorted edge and corner-sharing MgSi4 trigonal pyramids. There are a spread of Mg–Si bond distances ranging from 2.74–2.97 Å. There are four inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. The Si–Si bond length is 2.43 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to seven Mg2+ and two Si4- atoms. The Si–Si bond length is 2.51 Å. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. The Si–Si bond length is 2.42 Å. In the fourth Si4- site, Si4- is bonded in a 8-coordinate geometry to six Mg2+ and two Si4- atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.89–3.17 Å. In the second Mg2+ site, Mg2+ is bonded to four Si4- atoms to form MgSi4 tetrahedra that share corners with two equivalent MgSi4 tetrahedra, corners with four equivalent MgSi5 trigonal bipyramids, an edgeedge with one MgSi4 tetrahedra, and edges with three equivalent MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.63–2.77 Å. In the third Mg2+ site, Mg2+ is bonded to five Si4- atoms to form distorted MgSi5 trigonal bipyramids that share corners with four equivalent MgSi4 tetrahedra, edges with three equivalent MgSi4 tetrahedra, and edges with four equivalent MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.86–3.06 Å. In the fourth Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. There are two shorter (2.71 Å) and two longer (2.74 Å) Mg–Si bond lengths. In the fifth Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four Si4- atoms. There are two shorter (2.58 Å) and two longer (2.87 Å) Mg–Si bond lengths. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to nine Mg2+ atoms. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to nine Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a hexagonal planar geometry to six Si4- atoms. There are four shorter (2.95 Å) and two longer (2.96 Å) Mg–Si bond lengths. In the second Mg2+ site, Mg2+ is bonded to five Si4- atoms to form a mixture of distorted corner, edge, and face-sharing MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.89–3.04 Å. In the third Mg2+ site, Mg2+ is bonded in a square co-planar geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.95–3.07 Å. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 11-coordinate geometry to eleven Mg2+ atoms. In the second Si4- site, Si4- is bonded in a distorted q6 geometry to ten Mg2+ atoms. In the third Si4- site, Si4- is bonded in a distorted body-centered cubic geometry to eight Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.66–2.77 Å. In the second Mg2+ site, Mg2+ is bonded to five Si4- atoms to form distorted MgSi5 trigonal bipyramids that share corners with two equivalent MgSi4 tetrahedra, corners with two equivalent MgSi5 trigonal bipyramids, edges with four equivalent MgSi4 tetrahedra, and edges with three equivalent MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.73–2.94 Å. In the third Mg2+ site, Mg2+ is bonded to four Si4- atoms to form distorted MgSi4 tetrahedra that share corners with two equivalent MgSi4 tetrahedra, corners with two equivalent MgSi5 trigonal bipyramids, an edgeedge with one MgSi4 tetrahedra, and edges with four equivalent MgSi5 trigonal bipyramids. There are a spread of Mg–Si bond distances ranging from 2.80–2.97 Å. In the fourth Mg2+ site, Mg2+ is bonded in a distorted T-shaped geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.67–2.78 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 8-coordinate geometry to seven Mg2+ and one Si4- atom. The Si–Si bond length is 2.43 Å. In the second Si4- site, Si4- is bonded in a 8-coordinate geometry to eight Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.82–2.89 Å. In the second Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.83–3.20 Å. In the third Mg2+ site, Mg2+ is bonded in a distorted trigonal non-coplanar geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–3.01 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.76–3.13 Å. In the fifth Mg2+ site, Mg2+ is bonded in an L-shaped geometry to two Si4- atoms. There are one shorter (2.62 Å) and one longer (3.00 Å) Mg–Si bond lengths. In the sixth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.65–3.11 Å. In the seventh Mg2+ site, Mg2+ is bonded to five Si4- atoms to form distorted corner-sharing MgSi5 square pyramids. There are a spread of Mg–Si bond distances ranging from 2.74–3.05 Å. In the eighth Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.16 Å. There are four inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to seven Mg2+ and two Si4- atoms. There are one shorter (2.53 Å) and one longer (2.66 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded in a 10-coordinate geometry to nine Mg2+ and one Si4- atom. In the third Si4- site, Si4- is bonded in a 8-coordinate geometry to eight Mg2+ atoms. In the fourth Si4- site, Si4- is bonded in a 10-coordinate geometry to nine Mg2+ and one Si4- atom.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.66–3.01 Å. In the second Mg2+ site, Mg2+ is bonded in a distorted water-like geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.88–3.18 Å. In the third Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.76–2.96 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.87–3.11 Å. In the fifth Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.80–3.09 Å. In the sixth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.76–3.12 Å. In the seventh Mg2+ site, Mg2+ is bonded in a 3-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–2.77 Å. In the eighth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to three Si4- atoms. There are a spread of Mg–Si bond distances ranging from 2.70–3.00 Å. There are four inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 7-coordinate geometry to five Mg2+ and two Si4- atoms. There are one shorter (2.47 Å) and one longer (2.52 Å) Si–Si bond lengths. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Mg2+ and one Si4- atom. In the fourth Si4- site, Si4- is bonded in a 7-coordinate geometry to seven Mg2+ atoms.

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Materials Data on Mg2Si by Materials Project

Mg2Si crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to five equivalent Si4- atoms to form MgSi5 trigonal bipyramids that share corners with twelve equivalent MgSi6 octahedra, corners with eight equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi5 trigonal bipyramids, and faces with six equivalent MgSi6 octahedra. The corner-sharing octahedra tilt angles range from 28–63°. There are a spread of Mg–Si bond distances ranging from 2.65–3.08 Å. In the second Mg2+ site, Mg2+ is bonded to six equivalent Si4- atoms to form distorted MgSi6 octahedra that share corners with twelve equivalent MgSi6 octahedra, corners with twelve equivalent MgSi5 trigonal bipyramids, edges with six equivalent MgSi6 octahedra, faces with two equivalent MgSi6 octahedra, and faces with six equivalent MgSi5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–52°. There are a spread of Mg–Si bond distances ranging from 2.98–3.19 Å. Si4- is bonded in a 3-coordinate geometry to eleven Mg2+ atoms.

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