Materials Data on NaMg4(SiO3)6 by Materials Project

Abstract

NaMg4(SiO3)6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Na is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Na–O bond distances ranging from 2.43–2.93 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.15 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted 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 1.97–2.17 Å. In the third Mg site, Mg is bonded to six O atoms to form distorted 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 2.07–2.29 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 2.02–2.19 Å. There are three 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 56–60°. 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 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 third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 25–56°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. 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 distorted bent 150 degrees geometry to one Na and two Si atoms. In the sixth O site, O is bonded in a distorted T-shaped geometry to one Na, one Mg, and one Si atom. In the seventh O site, O is bonded to three Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg3Si tetrahedra. In the eighth O site, O is bonded in a 4-coordinate geometry to three Mg and one O atom. The O–O bond length is 1.51 Å. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to one Na, two Mg, and one Si atom.