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DOE OSTI · 1757849

Materials Data on Na5Fe3Ag2(As2O7)4 by Materials Project

Abstract

Na5Ag2Fe3(As2O7)4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.88 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.55 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–3.04 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six AsO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.12 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six AsO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.08 Å. Ag1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ag–O bond distances ranging from 2.40–3.13 Å. There are four inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent FeO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–51°. There are a spread of As–O bond distances ranging from 1.70–1.78 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent FeO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–50°. There are a spread of As–O bond distances ranging from 1.69–1.80 Å. In the third As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent FeO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–53°. There are a spread of As–O bond distances ranging from 1.70–1.81 Å. In the fourth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two FeO6 octahedra and a cornercorner with one AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of As–O bond distances ranging from 1.67–1.82 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one Ag1+, and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ag1+, and two As5+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, one Ag1+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Fe3+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two As5+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ag1+, and one As5+ atom. In the seventh O2- site, O2- is bonded to two Na1+, one Ag1+, and one As5+ atom to form distorted corner-sharing ONa2AgAs tetrahedra. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Fe3+, and one As5+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Fe3+, one Ag1+, and one As5+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+, one Fe3+, and one As5+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Fe3+, one Ag1+, and one As5+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Fe3+, one Ag1+, and one As5+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+, one Fe3+, and one As5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe3+, one Ag1+, and one As5+ atom.

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2020-09-03. Materials Data on Na5Fe3Ag2(As2O7)4 by Materials Project. https://doi.org/10.17188/1757849

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