Materials Data on Li2V2F7 by Materials Project

Abstract

Li2V2F7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form distorted LiF4 trigonal pyramids that share corners with two equivalent VF7 pentagonal bipyramids and an edgeedge with one VF7 pentagonal bipyramid. There are a spread of Li–F bond distances ranging from 1.86–1.98 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to five F1- atoms. There are a spread of Li–F bond distances ranging from 1.83–2.64 Å. There are two inequivalent V+2.50+ sites. In the first V+2.50+ site, V+2.50+ is bonded to seven F1- atoms to form distorted VF7 pentagonal bipyramids that share corners with two equivalent LiF4 trigonal pyramids and an edgeedge with one LiF4 trigonal pyramid. There are a spread of V–F bond distances ranging from 1.99–2.11 Å. In the second V+2.50+ site, V+2.50+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of V–F bond distances ranging from 2.08–2.50 Å. There are seven inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two V+2.50+ atoms. In the second F1- site, F1- is bonded in a trigonal non-coplanar geometry to one Li1+ and two V+2.50+ atoms. In the third F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two V+2.50+ atoms. In the fourth F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two V+2.50+ atoms. In the fifth F1- site, F1- is bonded in a trigonal planar geometry to one Li1+ and two V+2.50+ atoms. In the sixth F1- site, F1- is bonded in a distorted T-shaped geometry to one Li1+ and two V+2.50+ atoms. In the seventh F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two V+2.50+ atoms.