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DOE OSTI · 1284864

Materials Data on NaMg3Si4O11F by Materials Project

Abstract

NaMg3Si4O11F crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.24–2.72 Å. The Na–F bond length is 2.30 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.63 Å. There are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 1.91–2.70 Å. In the second Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Mg–O bond distances ranging from 2.09–2.45 Å. In the third Mg2+ site, Mg2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Mg–O bond distances ranging from 1.91–2.04 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with two equivalent SiO4F trigonal bipyramids, an edgeedge with one MgO6 octahedra, and edges with three SiO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 1.99–2.35 Å. In the fifth Mg2+ site, Mg2+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Mg–O bond distances ranging from 1.99–2.56 Å. The Mg–F bond length is 1.94 Å. In the sixth Mg2+ site, Mg2+ is bonded to four O2- and one F1- atom to form MgO4F trigonal bipyramids that share corners with three SiO4 tetrahedra and corners with two SiO4F trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 1.90–2.13 Å. The Mg–F bond length is 1.99 Å. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4F trigonal bipyramid and corners with two SiO5 trigonal bipyramids. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- and one F1- atom to form SiO4F trigonal bipyramids that share corners with two equivalent MgO6 octahedra, a cornercorner with one MgO4F trigonal bipyramid, a cornercorner with one SiO5 trigonal bipyramid, and an edgeedge with one SiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Si–O bond distances ranging from 1.59–1.83 Å. The Si–F bond length is 1.72 Å. In the third Si4+ site, Si4+ is bonded to five O2- atoms to form distorted SiO5 trigonal bipyramids that share a cornercorner with one SiO4 tetrahedra, corners with two SiO4F trigonal bipyramids, and edges with two equivalent MgO6 octahedra. There are a spread of Si–O bond distances ranging from 1.68–2.11 Å. In the fourth Si4+ site, Si4+ is bonded to five O2- atoms to form SiO5 trigonal bipyramids that share a cornercorner with one SiO4 tetrahedra, corners with two SiO5 trigonal bipyramids, an edgeedge with one MgO6 octahedra, and an edgeedge with one SiO4F trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.68–1.76 Å. In the fifth Si4+ site, Si4+ is bonded to three O2- and one F1- atom to form SiO3F tetrahedra that share a cornercorner with one SiO4 tetrahedra and a cornercorner with one SiO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.56–1.66 Å. The Si–F bond length is 1.71 Å. In the sixth Si4+ site, Si4+ is bonded to five O2- atoms to form distorted SiO5 trigonal bipyramids that share a cornercorner with one MgO4F trigonal bipyramid and edges with two SiO5 trigonal bipyramids. There are a spread of Si–O bond distances ranging from 1.60–1.82 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO3F tetrahedra, a cornercorner with one SiO5 trigonal bipyramid, and corners with two equivalent MgO4F trigonal bipyramids. There are a spread of Si–O bond distances ranging from 1.56–1.69 Å. In the eighth Si4+ site, Si4+ is bonded to five O2- atoms to form distorted SiO5 trigonal bipyramids that share corners with two SiO3F tetrahedra, a cornercorner with one SiO5 trigonal bipyramid, and an edgeedge with one SiO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.67–1.87 Å. There are twenty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, two Mg2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Mg2+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Mg2+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Mg2+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Si4+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and two Si4+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to two Mg2+ and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+ and two Si4+ atoms. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Mg2+, and two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one 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 one Na1+, one Mg2+, and two equivalent Si4+ atoms. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Na1+, one Mg2+, and one Si4+ atom. In the second F1- site, F1- is bonded in a water-like geometry to one Mg2+ and one Si4+ atom.

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2020-04-29. Materials Data on NaMg3Si4O11F by Materials Project. https://doi.org/10.17188/1284864

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