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DOE OSTI · 1295006

Materials Data on Li2VFeP2(O4F)2 by Materials Project

Abstract

Li2VFeP2(O4F)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form distorted LiO4F square pyramids that share corners with two equivalent VO4F2 octahedra, corners with two PO4 tetrahedra, an edgeedge with one VO4F2 octahedra, an edgeedge with one FeO4F2 octahedra, an edgeedge with one LiO4F square pyramid, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–61°. There are a spread of Li–O bond distances ranging from 2.08–2.25 Å. The Li–F bond length is 1.92 Å. In the second Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form distorted LiO4F square pyramids that share corners with two equivalent FeO4F2 octahedra, corners with two PO4 tetrahedra, an edgeedge with one VO4F2 octahedra, an edgeedge with one FeO4F2 octahedra, an edgeedge with one LiO4F square pyramid, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–60°. There are a spread of Li–O bond distances ranging from 2.08–2.24 Å. The Li–F bond length is 1.94 Å. There are two inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to four O2- and two equivalent F1- atoms to form VO4F2 octahedra that share corners with two equivalent FeO4F2 octahedra, corners with four equivalent PO4 tetrahedra, and edges with four LiO4F square pyramids. The corner-sharing octahedral tilt angles are 47°. There are two shorter (1.98 Å) and two longer (2.05 Å) V–O bond lengths. Both V–F bond lengths are 2.04 Å. In the second V3+ site, V3+ is bonded to four O2- and two equivalent F1- atoms to form VO4F2 octahedra that share corners with two equivalent FeO4F2 octahedra, corners with four equivalent LiO4F square pyramids, and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are two shorter (1.99 Å) and two longer (2.02 Å) V–O bond lengths. Both V–F bond lengths are 2.05 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four O2- and two equivalent F1- atoms to form FeO4F2 octahedra that share corners with two equivalent VO4F2 octahedra, corners with four equivalent PO4 tetrahedra, and edges with four LiO4F square pyramids. The corner-sharing octahedral tilt angles are 47°. There are two shorter (1.97 Å) and two longer (2.04 Å) Fe–O bond lengths. Both Fe–F bond lengths are 2.00 Å. In the second Fe3+ site, Fe3+ is bonded to four O2- and two equivalent F1- atoms to form FeO4F2 octahedra that share corners with two equivalent VO4F2 octahedra, corners with four equivalent LiO4F square pyramids, and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are two shorter (1.98 Å) and two longer (2.02 Å) Fe–O bond lengths. Both Fe–F bond lengths are 2.01 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO4F2 octahedra, corners with three FeO4F2 octahedra, corners with two LiO4F square pyramids, and an edgeedge with one LiO4F square pyramid. The corner-sharing octahedra tilt angles range from 30–53°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one FeO4F2 octahedra, corners with three VO4F2 octahedra, corners with two LiO4F square pyramids, and an edgeedge with one LiO4F square pyramid. The corner-sharing octahedra tilt angles range from 31–53°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+, one Fe3+, and one P5+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+, one V3+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one V3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V3+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one Fe3+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to one Li1+, one V3+, and one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+, one V3+, and one Fe3+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+, one V3+, and one Fe3+ atom.

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2020-06-04. Materials Data on Li2VFeP2(O4F)2 by Materials Project. https://doi.org/10.17188/1295006

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