DOI: 10.17188/1652196
title: Materials Data on KNaCaMg5(SiO3)8 by Materials Project

description: KNaCaMg5(SiO3)8 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. K is bonded in a 2-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.65–3.35 Å. Na is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Na–O bond distances ranging from 2.44–2.92 Å. Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.83 Å. There are five 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 five MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.11 Å. In the second 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 2.05–2.11 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 six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.12 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 2.01–2.19 Å. In the fifth 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 2.04–2.14 Å. There are eight 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 59–61°. There are a spread of Si–O bond distances ranging from 1.61–1.66 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 58–61°. There are a spread of Si–O bond distances ranging from 1.62–1.66 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 three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Si–O bond distances ranging from 1.62–1.66 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 59–61°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth 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 32–55°. There are a spread of Si–O bond distances ranging from 1.60–1.71 Å. In the sixth 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 33–58°. There are a spread of Si–O bond distances ranging from 1.60–1.69 Å. In the seventh 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 33–57°. There are a spread of Si–O bond distances ranging from 1.59–1.69 Å. In the eighth 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 33–55°. There are a spread of Si–O bond distances ranging from 1.60–1.71 Å. There are twenty-four inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one K, one Ca, and two Si atoms. In the second O site, O is bonded in a 2-coordinate geometry to one K, one Na, and two Si atoms. In the third O site, O is bonded in a 2-coordinate geometry to one K, one Na, and two Si atoms. In the fourth O site, O is bonded in a 2-coordinate geometry to one K, one Ca, and two Si atoms. In the fifth O site, O is bonded in a distorted rectangular see-saw-like geometry to one Na, two Mg, and one Si atom. In the sixth O site, O is bonded in a distorted rectangular see-saw-like geometry to one Ca, two Mg, and one Si atom. In the seventh O site, O is bonded in a distorted rectangular see-saw-like geometry to one Ca, two Mg, and one Si atom. In the eighth O site, O is bonded in a distorted rectangular see-saw-like geometry to one Na, two Mg, and one Si atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. 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 to three Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the twelfth O site, O is bonded to three Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the thirteenth O site, O is bonded to three Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fourteenth O site, O is bonded to three Mg and one Si atom to form a mixture of distorted corner and edge-sharing OMg3Si trigonal pyramids. In the fifteenth O site, O is bonded in a distorted T-shaped geometry to one Ca, one Mg, and one Si atom. In the sixteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Mg, and one Si atom. In the seventeenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Mg, and one Si atom. In the eighteenth O site, O is bonded in a distorted T-shaped geometry to one Ca, one Mg, and one Si atom. In the nineteenth O site, O is bonded in a 2-coordinate geometry to one K, one Ca, and two Si atoms. In the twentieth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Na, and two Si atoms. In the twenty-first O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Na, and two Si atoms. In the twenty-second O site, O is bonded in a 2-coordinate geometry to one K, one Ca, and two Si atoms. In the twenty-third O site, O is bonded in a 3-coordinate geometry to one K and two Si atoms. In the twenty-fourth O site, O is bonded in a 2-coordinate geometry to one K and two Si atoms.