Search NASA⌕ Search

SEARCH · Search NASA

Results for “Mg-O-Si”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Mg2+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.04–2.46 Å. Si4+ is bonded to six O2- atoms to form corner-sharing SiO6 octahedra. The corner-sharing octahedra tilt angles range from 33–34°. There is two shorter (1.80 Å) and four longer (1.82 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two equivalent Si4+ atoms to form distorted corner-sharing OMg2Si2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.18 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with eight equivalent SiO4 tetrahedra and edges with three equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.01–2.40 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with seven MgO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–67°. There are a spread of Si–O bond distances ranging from 1.60–1.69 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Mg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.05–2.30 Å. Si4+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing SiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. There is two shorter (1.81 Å) and four longer (1.82 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two equivalent Si4+ atoms to form distorted corner-sharing OMg2Si2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with six MgO6 octahedra. There are four shorter (2.07 Å) and two longer (2.14 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.12 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four equivalent SiO4 tetrahedra, and edges with seven MgO6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are two shorter (2.04 Å) and four longer (2.15 Å) Mg–O bond lengths. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with ten MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Si–O bond distances ranging from 1.65–1.72 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded to five Mg2+ atoms to form edge-sharing OMg5 square pyramids. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Mg2+ and two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 is Ilmenite-like structured and 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 to six O2- atoms to form MgO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with six MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. There are four shorter (2.02 Å) and two longer (2.17 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with six MgO6 octahedra. There are two shorter (2.33 Å) and four longer (2.34 Å) Mg–O bond lengths. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with six MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. There are four shorter (2.02 Å) and two longer (2.17 Å) Mg–O bond lengths. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with six MgO6 octahedra and edges with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–55°. There is one shorter (1.61 Å) and three longer (1.69 Å) Si–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 is Ilmenite-like structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, edges with four equivalent MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are two shorter (2.07 Å) and four longer (2.11 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with twelve equivalent MgO6 octahedra and corners with six equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Mg–O bond lengths are 2.24 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with six MgO6 octahedra and edges with three equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 54–57°. There is one shorter (1.63 Å) and three longer (1.67 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Mg2+ is bonded in a 1-coordinate geometry to nine O2- atoms. There are a spread of Mg–O bond distances ranging from 1.96–2.48 Å. Si4+ is bonded to six O2- atoms to form corner-sharing SiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is four shorter (1.75 Å) and two longer (1.79 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Mg2+ and two equivalent Si4+ atoms to form a mixture of distorted edge, face, and corner-sharing OMg4Si2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°. In the second O2- site, O2- is bonded to five equivalent Mg2+ and one Si4+ atom to form distorted OMg5Si octahedra that share corners with seventeen OMg4Si2 octahedra, edges with eight equivalent OMg5Si octahedra, and faces with four equivalent OMg4Si2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 is Ilmenite-like structured and crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two SiO4 tetrahedra, edges with five MgO6 octahedra, and edges with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Mg–O bond distances ranging from 2.05–2.14 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, edges with four equivalent MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. All Mg–O bond lengths are 2.10 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with twelve MgO6 octahedra and corners with six SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–57°. There are two shorter (2.24 Å) and four longer (2.26 Å) Mg–O bond lengths. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are four shorter (2.32 Å) and two longer (2.33 Å) Mg–O bond lengths. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with six MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. There are four shorter (2.02 Å) and two longer (2.13 Å) Mg–O bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with six MgO6 octahedra and edges with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–55°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with six MgO6 octahedra and edges with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–56°. There is one shorter (1.62 Å) and three longer (1.68 Å) Si–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with six equivalent MgO6 octahedra. All Mg–O bond lengths are 2.09 Å. Si4+ is bonded to four equivalent O2- atoms to form SiO4 tetrahedra that share corners with twelve equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Si–O bond lengths are 1.68 Å. O2- is bonded in a rectangular see-saw-like geometry to three equivalent Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 is Esseneite-derived structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.23 Å. In the second Mg2+ site, Mg2+ is bonded in a distorted rectangular see-saw-like geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 2.02–2.67 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent MgO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–61°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+ and two equivalent Si4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 is Ilmenite structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Mg2+ is bonded to six equivalent O2- atoms to form distorted MgO6 octahedra that share corners with nine equivalent SiO6 octahedra, edges with three equivalent MgO6 octahedra, and a faceface with one SiO6 octahedra. The corner-sharing octahedra tilt angles range from 40–60°. There are three shorter (2.01 Å) and three longer (2.20 Å) Mg–O bond lengths. Si4+ is bonded to six equivalent O2- atoms to form SiO6 octahedra that share corners with nine equivalent MgO6 octahedra, edges with three equivalent SiO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 40–60°. There is three shorter (1.78 Å) and three longer (1.85 Å) Si–O bond length. O2- is bonded in a distorted see-saw-like geometry to two equivalent Mg2+ and two equivalent Si4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent SiO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with four equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–23°. There are a spread of Mg–O bond distances ranging from 2.03–2.13 Å. In the second Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 1.96–2.49 Å. Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with two equivalent MgO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with three equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–23°. There are a spread of Si–O bond distances ranging from 1.72–1.90 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three Mg2+ and two equivalent Si4+ atoms to form a mixture of distorted edge and corner-sharing OMg3Si2 square pyramids. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Mg2+ and two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a distorted see-saw-like geometry to two Mg2+ and two equivalent Si4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with eight equivalent SiO4 tetrahedra and edges with three equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.50 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.17 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with seven MgO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–68°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OMg3Si trigonal pyramids. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted pentagonal planar geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 1.99–2.21 Å. In the second Mg2+ site, Mg2+ is bonded in a distorted pentagonal planar geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 1.97–2.18 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.72 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.72 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 is Esseneite-derived structured and crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.17–2.44 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.07 Å. In the third Mg2+ site, Mg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.08–2.72 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra and corners with two equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Si–O bond distances ranging from 1.63–1.70 Å. In the second Si4+ site, Si4+ is bonded to six O2- atoms to form corner-sharing SiO6 octahedra. There is two shorter (1.78 Å) and four longer (1.81 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four equivalent O2- atoms to form corner-sharing SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. All Si–O bond lengths are 1.65 Å. In the fourth Si4+ site, Si4+ is bonded to four equivalent O2- atoms to form SiO4 tetrahedra that share corners with four equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Si–O bond lengths are 1.65 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Mg2+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OMg3Si tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Mg2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Mg–O bond distances ranging from 2.07–2.50 Å. Si4+ is bonded to six O2- atoms to form edge-sharing SiO6 octahedra. There is two shorter (1.77 Å) and four longer (1.87 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to four equivalent Mg2+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2SiO4 by Materials Project

Mg2SiO4 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with three equivalent SiO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with three equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 7–53°. There are a spread of Mg–O bond distances ranging from 2.02–2.12 Å. In the second Mg2+ site, Mg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.03–2.59 Å. Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with three equivalent MgO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with three equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 7–53°. There are a spread of Si–O bond distances ranging from 1.73–1.90 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to three Mg2+ and two equivalent Si4+ atoms to form distorted OMg3Si2 square pyramids that share corners with five equivalent OMg3Si tetrahedra, corners with two equivalent OMg4Si trigonal bipyramids, edges with two equivalent OMg3Si2 square pyramids, an edgeedge with one OMg3Si tetrahedra, and edges with three equivalent OMg4Si trigonal bipyramids. In the third O2- site, O2- is bonded to four Mg2+ and one Si4+ atom to form distorted OMg4Si trigonal bipyramids that share corners with two equivalent OMg3Si2 square pyramids, corners with five equivalent OMg3Si tetrahedra, edges with three equivalent OMg3Si2 square pyramids, an edgeedge with one OMg3Si tetrahedra, and edges with two equivalent OMg4Si trigonal bipyramids. In the fourth O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form distorted OMg3Si tetrahedra that share corners with five equivalent OMg3Si2 square pyramids, corners with two equivalent OMg3Si tetrahedra, corners with five equivalent OMg4Si trigonal bipyramids, an edgeedge with one OMg3Si2 square pyramid, and an edgeedge with one OMg4Si trigonal bipyramid.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSiO3 by Materials Project

MgSiO3 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with three equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 2.04–2.23 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted MgO5 square pyramids that share corners with four SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.30 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.27 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with two SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.35 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.24 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with two SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.36 Å. In the seventh Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.23 Å. In the eighth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 2.02–2.33 Å. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–61°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one MgO5 square pyramid, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 25–60°. There are a spread of Si–O bond distances ranging from 1.60–1.69 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–62°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra, a cornercorner with one MgO5 square pyramid, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 24–61°. There are a spread of Si–O bond distances ranging from 1.60–1.68 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 25–61°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 25–61°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–61°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra, corners with two equivalent SiO4 tetrahedra, and an edgeedge with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 27–61°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form distorted corner-sharing OMg3Si trigonal pyramids. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Mg2+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the tenth O2- site, O2- is bonded to three Mg2+ and one Si4+ atom to form distorted corner-sharing OMg3Si trigonal pyramids. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a distorted T-shaped geometry to two Mg2+ and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent Si4+ atoms.

36 MATERIALS SCIENCE↗