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DOE OSTI · 1286443

Materials Data on Mg16Si7HO32 by Materials Project

Abstract

Mg16Si7HO32 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.16 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.20 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.19 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with three MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.17 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four SiO4 tetrahedra, and edges with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mg–O bond distances ranging from 2.04–2.20 Å. In the sixth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mg–O bond distances ranging from 1.99–2.18 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mg–O bond distances ranging from 1.99–2.18 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four SiO4 tetrahedra, and edges with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mg–O bond distances ranging from 2.04–2.20 Å. In the ninth Mg site, Mg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.98–2.34 Å. In the tenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with five SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.94–2.21 Å. In the eleventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with four MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.44 Å. In the twelfth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with five SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.96–2.13 Å. In the thirteenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with three SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.92–2.19 Å. In the fourteenth Mg site, Mg is bonded in a 7-coordinate geometry to one H and six O atoms. The Mg–H bond length is 2.11 Å. There are a spread of Mg–O bond distances ranging from 1.98–2.26 Å. In the fifteenth Mg site, Mg is bonded in a 7-coordinate geometry to one H and six O atoms. The Mg–H bond length is 2.20 Å. There are a spread of Mg–O bond distances ranging from 1.99–2.25 Å. In the sixteenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with three SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.92–2.18 Å. There are seven inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with eight MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–62°. There are a spread of Si–O bond distances ranging from 1.66–1.70 Å. In the second Si site, Si is bonded to four O 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 45–61°. There are a spread of Si–O bond distances ranging from 1.65–1.76 Å. In the third Si site, Si is bonded to four O 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 46–62°. There is three shorter (1.64 Å) and one longer (1.74 Å) Si–O bond length. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with eight MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–59°. There is three shorter (1.66 Å) and one longer (1.71 Å) Si–O bond length. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with nine MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–58°. There are a spread of Si–O bond distances ranging from 1.66–1.73 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with seven MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–60°. There are a spread of Si–O bond distances ranging from 1.65–1.71 Å. In the seventh Si site, Si is bonded to four O atoms to form distorted SiO4 tetrahedra that share corners with six MgO6 octahedra. The corner-sharing octahedra tilt angles range from 42–57°. There are a spread of Si–O bond distances ranging from 1.56–1.85 Å. H is bonded in a single-bond geometry to two Mg and one O atom. The H–O bond length is 1.00 Å. There are thirty-two inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to one Mg and two Si atoms. In the second O site, O is bonded in a trigonal planar geometry to one Mg and two Si atoms. In the third O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. In the fourth O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. In the fifth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the sixth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the seventh O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the eighth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the ninth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the tenth O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the eleventh O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the twelfth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. 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 rectangular see-saw-like geometry to three Mg and one Si atom. In the fifteenth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the sixteenth O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the seventeenth O site, O is bonded in a trigonal planar geometry to one Mg and two Si atoms. In the eighteenth O site, O is bonded in a bent 150 degrees geometry to one Mg and one Si atom. In the nineteenth O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. In the twentieth O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. In the twenty-first O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-second O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-third O site, O is bonded in a distorted single-bond geometry to three Mg, one Si, and one H atom. In the twenty-fourth O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the twenty-fifth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-sixth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-seventh O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-eighth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the twenty-ninth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the thirtieth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the thirty-first O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the thirty-second O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom.

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2020-04-30. Materials Data on Mg16Si7HO32 by Materials Project. https://doi.org/10.17188/1286443

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