DOI: 10.17188/1200229
title: Materials Data on Mg16Si8HO32 by Materials Project

description: Mg16Si8HO32 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first 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 seven MgO6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are a spread of Mg–O bond distances ranging from 2.04–2.18 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 six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.19 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.16 Å. In the fourth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.40 Å. In the fifth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four SiO4 tetrahedra, and edges with seven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–16°. There are a spread of Mg–O bond distances ranging from 2.07–2.17 Å. In the sixth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.16 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are one shorter (2.07 Å) and five longer (2.13 Å) Mg–O bond lengths. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.14 Å. There are four inequivalent Si sites. In the first 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 46–61°. There are a spread of Si–O bond distances ranging from 1.65–1.72 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 47–61°. There are a spread of Si–O bond distances ranging from 1.66–1.73 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 are a spread of Si–O bond distances ranging from 1.66–1.74 Å. In the fourth 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 46–61°. There are a spread of Si–O bond distances ranging from 1.66–1.73 Å. H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. There are sixteen 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 rectangular see-saw-like geometry to three Mg and one Si atom. 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 rectangular see-saw-like geometry to three Mg and one Si atom. In the fifth O site, O is bonded in a square pyramidal geometry to five Mg atoms. In the sixth O site, O is bonded in a single-bond geometry to five Mg and one H atom. In the seventh O site, O is bonded in a trigonal planar geometry to one Mg and two equivalent Si atoms. In the eighth O site, O is bonded in a trigonal planar geometry to one Mg and two equivalent Si atoms. In the ninth O site, O is bonded in a trigonal planar geometry to one Mg and two equivalent Si atoms. In the tenth O site, O is bonded in a trigonal planar geometry to one Mg and two equivalent Si atoms. In the eleventh O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. In the twelfth O site, O is bonded to five Mg atoms to form edge-sharing OMg5 square pyramids. 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 distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the sixteenth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom.