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DOE OSTI · 1665302

Materials Data on Na2NiPO4F by Materials Project

Abstract

Na2NiPO4F crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.85 Å. There are one shorter (2.38 Å) and one longer (2.40 Å) Na–F bond lengths. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.38–2.95 Å. There are one shorter (2.36 Å) and one longer (2.61 Å) Na–F bond lengths. In the third Na1+ site, Na1+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.83 Å. There are one shorter (2.39 Å) and one longer (2.40 Å) Na–F bond lengths. In the fourth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.40–2.95 Å. There are one shorter (2.37 Å) and one longer (2.64 Å) Na–F bond lengths. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded to four O2- and two F1- atoms to form distorted NiO4F2 octahedra that share a cornercorner with one NiO4F2 octahedra, corners with four PO4 tetrahedra, and a faceface with one NiO4F2 octahedra. The corner-sharing octahedral tilt angles are 67°. There are a spread of Ni–O bond distances ranging from 2.06–2.12 Å. There are one shorter (2.06 Å) and one longer (2.11 Å) Ni–F bond lengths. In the second Ni2+ site, Ni2+ is bonded to four O2- and two F1- atoms to form distorted NiO4F2 octahedra that share a cornercorner with one NiO4F2 octahedra, corners with four PO4 tetrahedra, and a faceface with one NiO4F2 octahedra. The corner-sharing octahedral tilt angles are 67°. There are a spread of Ni–O bond distances ranging from 2.05–2.12 Å. There are one shorter (2.04 Å) and one longer (2.12 Å) Ni–F bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four NiO4F2 octahedra. The corner-sharing octahedra tilt angles range from 39–52°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with four NiO4F2 octahedra. The corner-sharing octahedra tilt angles range from 37–53°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two Na1+, one Ni2+, and one P5+ atom to form distorted ONa2NiP tetrahedra that share corners with three equivalent FNa4Ni2 octahedra. The corner-sharing octahedra tilt angles range from 4–58°. In the second O2- site, O2- is bonded to two Na1+, one Ni2+, and one P5+ atom to form distorted ONa2NiP tetrahedra that share corners with three equivalent FNa4Ni2 octahedra. The corner-sharing octahedra tilt angles range from 4–59°. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two Ni2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Ni2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, two Ni2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Ni2+, and one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four Na1+ and two Ni2+ atoms to form FNa4Ni2 octahedra that share corners with six ONa2NiP tetrahedra. In the second F1- site, F1- is bonded in a 6-coordinate geometry to four Na1+ and two Ni2+ atoms.

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2020-04-29. Materials Data on Na2NiPO4F by Materials Project. https://doi.org/10.17188/1665302

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