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DOE OSTI · 1297816

Materials Data on Li2VP2O7 by Materials Project

Abstract

Li2VP2O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra, corners with four PO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 1.88–2.02 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 tetrahedra that share corners with two equivalent LiO4 tetrahedra and corners with four PO4 tetrahedra. There is two shorter (1.89 Å) and two longer (2.01 Å) Li–O bond length. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent LiO4 tetrahedra and corners with four PO4 tetrahedra. All Li–O bond lengths are 2.01 Å. V2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of V–O bond distances ranging from 2.11–2.60 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 PO4 tetrahedra, corners with three LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. There are a spread of P–O bond distances ranging from 1.51–1.65 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one PO4 tetrahedra, corners with three LiO4 tetrahedra, and a cornercorner with one LiO4 trigonal pyramid. There are a spread of P–O bond distances ranging from 1.50–1.65 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V2+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V2+, and one P5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two equivalent V2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Li1+ and one P5+ atom.

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2020-07-15. Materials Data on Li2VP2O7 by Materials Project. https://doi.org/10.17188/1297816

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