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DOE OSTI · 1666900

Materials Data on Na2Ca4YZrSi4(O5F)3 by Materials Project

Abstract

Na2Ca4YZrSi4(O5F)3 is Esseneite-derived structured and 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 three O2- and three F1- atoms. There are a spread of Na–O bond distances ranging from 2.47–2.71 Å. There are a spread of Na–F bond distances ranging from 2.31–2.44 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- and two equivalent F1- atoms. There are a spread of Na–O bond distances ranging from 2.44–3.03 Å. There are one shorter (2.35 Å) and one longer (2.36 Å) Na–F bond lengths. There are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to three O2- and three F1- atoms to form distorted CaO3F3 octahedra that share corners with two equivalent YO5F octahedra, corners with three SiO4 tetrahedra, an edgeedge with one CaO3F3 octahedra, and an edgeedge with one ZrO6 octahedra. The corner-sharing octahedra tilt angles range from 58–65°. There are a spread of Ca–O bond distances ranging from 2.30–2.41 Å. There are a spread of Ca–F bond distances ranging from 2.32–2.36 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to seven O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.33–2.79 Å. The Ca–F bond length is 2.22 Å. In the third Ca2+ site, Ca2+ is bonded to five O2- and one F1- atom to form CaO5F octahedra that share corners with two equivalent ZrO6 octahedra, corners with three SiO4 tetrahedra, an edgeedge with one CaO5F octahedra, and an edgeedge with one YO5F octahedra. The corner-sharing octahedra tilt angles range from 53–61°. There are a spread of Ca–O bond distances ranging from 2.29–2.51 Å. The Ca–F bond length is 2.31 Å. In the fourth 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 2.31–2.55 Å. The Ca–F bond length is 2.26 Å. Y3+ is bonded to five O2- and one F1- atom to form YO5F octahedra that share corners with two equivalent CaO3F3 octahedra, corners with five SiO4 tetrahedra, and an edgeedge with one CaO5F octahedra. The corner-sharing octahedra tilt angles range from 58–65°. There are a spread of Y–O bond distances ranging from 2.26–2.29 Å. The Y–F bond length is 2.31 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with two equivalent CaO5F octahedra, corners with five SiO4 tetrahedra, and an edgeedge with one CaO3F3 octahedra. The corner-sharing octahedra tilt angles range from 53–61°. There are a spread of Zr–O bond distances ranging from 1.95–2.37 Å. There are four 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 YO5F octahedra, a cornercorner with one ZrO6 octahedra, corners with two CaO3F3 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–75°. There are a spread of Si–O bond distances ranging from 1.61–1.66 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, a cornercorner with one ZrO6 octahedra, corners with two equivalent YO5F octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–54°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO3F3 octahedra, a cornercorner with one YO5F octahedra, corners with two equivalent ZrO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–54°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one YO5F octahedra, a cornercorner with one ZrO6 octahedra, corners with two CaO3F3 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–74°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Zr4+, and one Si4+ atom. In the second O2- site, O2- is bonded to one Na1+, two equivalent Ca2+, and one Zr4+ atom to form distorted ONaCa2Zr tetrahedra that share corners with two equivalent FNa2Ca2 tetrahedra, an edgeedge with one ONaCa2Zr tetrahedra, and an edgeedge with one FNa2Ca2 tetrahedra. 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 distorted linear geometry to one Ca2+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Zr4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ca2+, one Zr4+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Y3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Y3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Zr4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Y3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Y3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Zr4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Ca2+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Y3+, and one Si4+ atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded to one Na1+, two equivalent Ca2+, and one Y3+ atom to form a mixture of edge and corner-sharing FNaCa2Y tetrahedra. In the second F1- site, F1- is bonded to two equivalent Na1+ and two Ca2+ atoms to form FNa2Ca2 tetrahedra that share corners with two equivalent FNaCa2Y tetrahedra and edges with two FNa2Ca2 tetrahedra. In the third F1- site, F1- is bonded to two equivalent Na1+ and two Ca2+ atoms to form distorted FNa2Ca2 tetrahedra that share corners with two equivalent ONaCa2Zr tetrahedra, an edgeedge with one ONaCa2Zr tetrahedra, and an edgeedge with one FNa2Ca2 tetrahedra.

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2020-04-29. Materials Data on Na2Ca4YZrSi4(O5F)3 by Materials Project. https://doi.org/10.17188/1666900

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