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DOE OSTI · 1699932

Materials Data on Mg2(SiO3)3 by Materials Project

Abstract

Mg2(SiO3)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.14 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with five MgO6 octahedra, and an edgeedge with one MgO5 square pyramid. There are a spread of Mg–O bond distances ranging from 2.06–2.15 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with three MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 1.99–2.16 Å. In the fourth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with four SiO4 tetrahedra and edges with three MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.11 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–59°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–60°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–61°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, a cornercorner with one MgO5 square pyramid, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. There are eighteen inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the second O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the third O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the fourth O site, O is bonded in a distorted trigonal planar geometry to two Mg and one Si atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the sixth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the seventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the ninth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the tenth O site, O is bonded in a single-bond geometry to one Mg atom. In the eleventh O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the twelfth O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the thirteenth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the fourteenth O site, O is bonded in a distorted trigonal planar geometry to two Mg and one Si atom. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the sixteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the seventeenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to two Si atoms.

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2020-04-29. Materials Data on Mg2(SiO3)3 by Materials Project. https://doi.org/10.17188/1699932

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