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DOE OSTI · 1758357

Materials Data on NaCa2SiO4F by Materials Project

Abstract

Ca2NaSiO4F crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to three O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.20–2.72 Å. There are one shorter (2.32 Å) and one longer (2.36 Å) Na–F bond lengths. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to three O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.25–2.91 Å. There are one shorter (2.28 Å) and one longer (2.71 Å) Na–F bond lengths. In the third 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 2.27–2.74 Å. The Na–F bond length is 2.34 Å. In the fourth Na1+ site, Na1+ is bonded in a rectangular see-saw-like geometry to three O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.24–2.29 Å. The Na–F bond length is 2.20 Å. There are eight inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to five O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.24–2.59 Å. The Ca–F bond length is 2.43 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.25–2.73 Å. The Ca–F bond length is 2.32 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.20–2.94 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to three O2- and two F1- atoms. There are a spread of Ca–O bond distances ranging from 2.18–2.67 Å. There are one shorter (2.24 Å) and one longer (2.44 Å) Ca–F bond lengths. In the fifth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to four O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.22–2.54 Å. The Ca–F bond length is 2.39 Å. In the sixth Ca2+ site, Ca2+ is bonded to five O2- and one F1- atom to form CaO5F octahedra that share corners with four SiO3F tetrahedra. There are a spread of Ca–O bond distances ranging from 2.23–2.59 Å. The Ca–F bond length is 2.64 Å. In the seventh Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to three O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.30–2.35 Å. The Ca–F bond length is 2.25 Å. In the eighth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to four O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.22–2.43 Å. The Ca–F bond length is 2.68 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to three O2- and one F1- atom to form SiO3F tetrahedra that share a cornercorner with one CaO5F octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. There is two shorter (1.62 Å) and one longer (1.64 Å) Si–O bond length. The Si–F bond length is 1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO5F octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO5F octahedra and a cornercorner with one SiO3F tetrahedra. The corner-sharing octahedral tilt angles are 70°. There are a spread of Si–O bond distances ranging from 1.62–1.75 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO5F octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, three Ca2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded to four Ca2+ atoms to form OCa4 tetrahedra that share a cornercorner with one ONaCa4 trigonal bipyramid and a cornercorner with one ONaCa2Si trigonal pyramid. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Ca2+ atoms. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded to one Na1+ and four Ca2+ atoms to form distorted ONaCa4 trigonal bipyramids that share a cornercorner with one OCa4 tetrahedra, a cornercorner with one ONaCa2Si trigonal pyramid, and corners with two equivalent FNa2Ca2 trigonal pyramids. In the thirteenth O2- site, O2- is bonded to one Na1+, two Ca2+, and one Si4+ atom to form distorted ONaCa2Si trigonal pyramids that share a cornercorner with one OCa4 tetrahedra and a cornercorner with one ONaCa4 trigonal bipyramid. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, three Ca2+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ca2+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two Ca2+, and one Si4+ atom. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded to two Na1+ and two Ca2+ atoms to form distorted FNa2Ca2 trigonal pyramids that share corners with two equivalent ONaCa4 trigonal bipyramids. In the second F1- site, F1- is bonded in a 4-coordinate geometry to two Na1+ and two Ca2+ atoms. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Na1+, one Ca2+, and one Si4+ atom. In the fourth F1- site, F1- is bonded in a 4-coordinate geometry to one Na1+ and three Ca2+ atoms.

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2020-09-03. Materials Data on NaCa2SiO4F by Materials Project. https://doi.org/10.17188/1758357

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