DOE OSTI2020
Li2VF4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six VF6 octahedra, corners with two equivalent LiF4 tetrahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–72°. There are a spread of Li–F bond distances ranging from 1.86–2.01 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six VF6 octahedra, corners with two equivalent LiF4 tetrahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–71°. There are a spread of Li–F bond distances ranging from 1.86–2.01 Å. In the third Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six VF6 octahedra, corners with two equivalent LiF4 tetrahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–70°. There are a spread of Li–F bond distances ranging from 1.86–2.01 Å. In the fourth Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six VF6 octahedra, corners with two equivalent LiF4 tetrahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–74°. There are a spread of Li–F bond distances ranging from 1.86–2.01 Å. There are two inequivalent V2+ sites. In the first V2+ site, V2+ is bonded to six F1- atoms to form VF6 octahedra that share corners with twelve LiF4 tetrahedra and edges with two equivalent VF6 octahedra. There are a spread of V–F bond distances ranging from 2.09–2.17 Å. In the second V2+ site, V2+ is bonded to six F1- atoms to form VF6 octahedra that share corners with twelve LiF4 tetrahedra and edges with two equivalent VF6 octahedra. There are a spread of V–F bond distances ranging from 2.09–2.17 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded to two equivalent Li1+ and two equivalent V2+ atoms to form a mixture of distorted corner and edge-sharing FLi2V2 tetrahedra. In the second F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one V2+ atom. In the third F1- site, F1- is bonded to two equivalent Li1+ and two equivalent V2+ atoms to form a mixture of distorted corner and edge-sharing FLi2V2 tetrahedra. In the fourth F1- site, F1- is bonded to two equivalent Li1+ and two equivalent V2+ atoms to form a mixture of distorted corner and edge-sharing FLi2V2 tetrahedra. In the fifth F1- site, F1- is bonded to two equivalent Li1+ and two equivalent V2+ atoms to form a mixture of distorted corner and edge-sharing FLi2V2 tetrahedra. In the sixth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one V2+ atom. In the seventh F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one V2+ atom. In the eighth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one V2+ atom.