DOI: 10.17188/1723471
title: Materials Data on Na2CaMg5Si8(O11F)2 by Materials Project

description: Na2CaMg5Si8O22F2 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 1-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.44–3.05 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–3.00 Å. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.94 Å. There are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- and two F1- atoms to form MgO4F2 octahedra that share corners with four SiO4 tetrahedra and edges with five MgO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.09 Å. There are one shorter (2.06 Å) and one longer (2.08 Å) Mg–F bond lengths. In the second Mg2+ site, Mg2+ is bonded to four O2- and two F1- atoms to form MgO4F2 octahedra that share corners with four SiO4 tetrahedra and edges with five MgO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. There are one shorter (2.11 Å) and one longer (2.13 Å) Mg–F bond lengths. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with three MgO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.20 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with three MgO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.28 Å. In the fifth Mg2+ site, Mg2+ is bonded to four O2- and two F1- atoms to form MgO4F2 octahedra that share corners with four SiO4 tetrahedra and edges with six MgO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.10 Å. There are one shorter (2.03 Å) and one longer (2.04 Å) Mg–F bond lengths. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra 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 1.62–1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra 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 1.62–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–62°. There is one shorter (1.61 Å) and three longer (1.65 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–62°. There is one shorter (1.61 Å) and three longer (1.65 Å) Si–O bond length. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–57°. There are a spread of Si–O bond distances ranging from 1.59–1.70 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–57°. There are a spread of Si–O bond distances ranging from 1.59–1.68 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–56°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO4F2 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 1.61–1.71 Å. There are twenty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two Si4+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Mg2+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two Mg2+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Mg2+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Na1+, one Mg2+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to three Mg2+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to three Mg2+ atoms.