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DOE OSTI · 1741475

Materials Data on Na22CaFe6P12(O8F)6 by Materials Project

Abstract

Na22CaFe6P12(O8F)6 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are ten inequivalent Na sites. In the first Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.29–2.59 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.28–2.53 Å. In the third Na site, Na is bonded to three equivalent O and three equivalent F atoms to form distorted NaO3F3 octahedra that share corners with three equivalent FeO5F octahedra and corners with three equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. All Na–O bond lengths are 2.46 Å. All Na–F bond lengths are 2.50 Å. In the fourth Na site, Na is bonded to three equivalent O and three equivalent F atoms to form distorted NaO3F3 octahedra that share corners with three equivalent FeO5F octahedra, corners with three equivalent PO4 tetrahedra, and edges with three equivalent NaO5F octahedra. The corner-sharing octahedral tilt angles are 20°. All Na–O bond lengths are 2.51 Å. All Na–F bond lengths are 2.47 Å. In the fifth Na site, Na is bonded in a 6-coordinate geometry to six O atoms. All Na–O bond lengths are 2.54 Å. In the sixth Na site, Na is bonded to five O and one F atom to form distorted NaO5F octahedra that share corners with five PO4 tetrahedra, an edgeedge with one NaO3F3 octahedra, and edges with two equivalent FeO5F octahedra. There are a spread of Na–O bond distances ranging from 2.25–2.62 Å. The Na–F bond length is 2.36 Å. In the seventh Na site, Na is bonded in a 6-coordinate geometry to five O and one F atom. There are a spread of Na–O bond distances ranging from 2.26–2.58 Å. The Na–F bond length is 2.46 Å. In the eighth Na site, Na is bonded in a 6-coordinate geometry to six O and three equivalent F atoms. There are three shorter (2.52 Å) and three longer (2.86 Å) Na–O bond lengths. All Na–F bond lengths are 2.37 Å. In the ninth Na site, Na is bonded in a 4-coordinate geometry to four O and two equivalent F atoms. There are a spread of Na–O bond distances ranging from 2.30–2.71 Å. There are one shorter (2.37 Å) and one longer (2.74 Å) Na–F bond lengths. In the tenth Na site, Na is bonded in a 6-coordinate geometry to four O and two equivalent F atoms. There are a spread of Na–O bond distances ranging from 2.31–2.74 Å. There are one shorter (2.31 Å) and one longer (2.67 Å) Na–F bond lengths. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six PO4 tetrahedra. There are three shorter (2.40 Å) and three longer (2.41 Å) Ca–O bond lengths. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to five O and one F atom to form FeO5F octahedra that share a cornercorner with one NaO3F3 octahedra and corners with five PO4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. There are a spread of Fe–O bond distances ranging from 1.97–2.08 Å. The Fe–F bond length is 2.09 Å. In the second Fe site, Fe is bonded to five O and one F atom to form FeO5F octahedra that share a cornercorner with one NaO3F3 octahedra, corners with five PO4 tetrahedra, and edges with two equivalent NaO5F octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Fe–O bond distances ranging from 1.97–2.14 Å. The Fe–F bond length is 2.02 Å. There are four inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one NaO5F octahedra, a cornercorner with one CaO6 octahedra, and corners with two FeO5F octahedra. The corner-sharing octahedra tilt angles range from 37–54°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one NaO5F octahedra, a cornercorner with one CaO6 octahedra, and corners with two FeO5F octahedra. The corner-sharing octahedra tilt angles range from 36–74°. There are a spread of P–O bond distances ranging from 1.52–1.59 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with three NaO3F3 octahedra and corners with three FeO5F octahedra. The corner-sharing octahedra tilt angles range from 34–63°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with two NaO3F3 octahedra and corners with three FeO5F octahedra. The corner-sharing octahedra tilt angles range from 32–61°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are sixteen inequivalent O sites. In the first O site, O is bonded in a distorted rectangular see-saw-like geometry to two Na, one Ca, and one P atom. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to two Na, one Ca, and one P atom. In the third O site, O is bonded in a 4-coordinate geometry to two Na, one Fe, and one P atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two Na, one Fe, and one P atom. In the fifth O site, O is bonded in a 3-coordinate geometry to one Na, one Fe, and one P atom. In the sixth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Na, one Fe, and one P atom. In the seventh O site, O is bonded in a 3-coordinate geometry to two Na and one P atom. In the eighth O site, O is bonded in a 3-coordinate geometry to two Na and one P atom. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Na and one P atom. In the tenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Na and one P atom. In the eleventh O site, O is bonded in a 5-coordinate geometry to three Na, one Fe, and one P atom. In the twelfth O site, O is bonded in a 5-coordinate geometry to three Na, one Fe, and one P atom. In the thirteenth O site, O is bonded in a distorted trigonal pyramidal geometry to two Na, one Fe, and one P atom. In the fourteenth O site, O is bonded in a 2-coordinate geometry to three Na, one Fe, and one P atom. In the fifteenth O site, O is bonded in a 4-coordinate geometry to two Na, one Fe, and one P atom. In the sixteenth O site, O is bonded in a 4-coordinate geometry to two Na, one Fe, and one P atom. There are two inequivalent F sites. In the first F site, F is bonded in a 6-coordinate geometry to five Na and one Fe atom. In the second F site, F is bonded in a 5-coordinate geometry to four Na and one Fe atom.

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2020-04-30. Materials Data on Na22CaFe6P12(O8F)6 by Materials Project. https://doi.org/10.17188/1741475

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