DOE OSTI2020
Li3V2(OF)4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 5-coordinate geometry to three O2- and two F1- atoms. There are a spread of Li–O bond distances ranging from 2.09–2.54 Å. There is one shorter (1.83 Å) and one longer (1.86 Å) Li–F bond length. In the second Li1+ site, Li1+ is bonded in a 5-coordinate geometry to three O2- and two F1- atoms. There are two shorter (1.95 Å) and one longer (2.23 Å) Li–O bond lengths. There are one shorter (1.90 Å) and one longer (2.15 Å) Li–F bond lengths. In the third Li1+ site, Li1+ is bonded in a 1-coordinate geometry to one O2- and five F1- atoms. The Li–O bond length is 2.53 Å. There are a spread of Li–F bond distances ranging from 1.84–2.43 Å. There are two inequivalent V+4.50+ sites. In the first V+4.50+ site, V+4.50+ is bonded to four O2- and two F1- atoms to form a mixture of distorted edge and corner-sharing VO4F2 octahedra. The corner-sharing octahedral tilt angles are 32°. There are a spread of V–O bond distances ranging from 1.68–2.31 Å. There is one shorter (1.99 Å) and one longer (2.00 Å) V–F bond length. In the second V+4.50+ site, V+4.50+ is bonded to four O2- and two F1- atoms to form a mixture of distorted edge and corner-sharing VO4F2 octahedra. The corner-sharing octahedral tilt angles are 27°. There are a spread of V–O bond distances ranging from 1.70–2.24 Å. There is one shorter (1.86 Å) and one longer (1.98 Å) V–F bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three V+4.50+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to four Li1+ and one V+4.50+ atom. In the third O2- site, O2- is bonded to three Li1+ and one V+4.50+ atom to form distorted OLi3V trigonal pyramids that share corners with two equivalent FLi3V tetrahedra and corners with two equivalent OLi3V trigonal pyramids. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three V+4.50+ atoms. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to one Li1+ and one V+4.50+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one V+4.50+ atom. In the third F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one V+4.50+ atom. In the fourth F1- site, F1- is bonded to three Li1+ and one V+4.50+ atom to form distorted FLi3V tetrahedra that share corners with two equivalent FLi3V tetrahedra and corners with two equivalent OLi3V trigonal pyramids.