DOE OSTI2020
Li2MnF5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with six MnF5 square pyramids and an edgeedge with one LiF6 octahedra. There are a spread of Li–F bond distances ranging from 1.99–2.28 Å. In the second Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.89–2.13 Å. In the third Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.85–2.21 Å. In the fourth Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with two equivalent LiF6 octahedra and corners with six MnF5 square pyramids. The corner-sharing octahedra tilt angles range from 70–73°. There are a spread of Li–F bond distances ranging from 1.97–2.39 Å. In the fifth Li1+ site, Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with two equivalent LiF6 octahedra and corners with six MnF5 square pyramids. The corner-sharing octahedra tilt angles range from 70–73°. There are a spread of Li–F bond distances ranging from 1.97–2.57 Å. In the sixth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of Li–F bond distances ranging from 1.93–2.22 Å. There are three inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to five F1- atoms to form MnF5 square pyramids that share corners with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 23–70°. There are a spread of Mn–F bond distances ranging from 1.85–2.09 Å. In the second Mn3+ site, Mn3+ is bonded to five F1- atoms to form MnF5 square pyramids that share corners with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 36–56°. There are a spread of Mn–F bond distances ranging from 1.87–2.08 Å. In the third Mn3+ site, Mn3+ is bonded to five F1- atoms to form MnF5 square pyramids that share corners with six LiF6 octahedra. The corner-sharing octahedra tilt angles range from 23–57°. There are a spread of Mn–F bond distances ranging from 1.86–2.07 Å. There are fifteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted T-shaped geometry to two Li1+ and one Mn3+ atom. In the second F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and one Mn3+ atom. In the third F1- site, F1- is bonded in a distorted see-saw-like geometry to three Li1+ and one Mn3+ atom. In the fourth F1- site, F1- is bonded in a distorted trigonal planar geometry to two equivalent Li1+ and one Mn3+ atom. In the fifth F1- site, F1- is bonded in a distorted T-shaped geometry to two Li1+ and one Mn3+ atom. In the sixth F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Mn3+ atom. In the seventh F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to two Li1+ and one Mn3+ atom. In the eighth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Mn3+ atom. In the ninth F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Mn3+ atom. In the tenth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Mn3+ atom. In the eleventh F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Mn3+ atom. In the twelfth F1- site, F1- is bonded in a distorted T-shaped geometry to two Li1+ and one Mn3+ atom. In the thirteenth F1- site, F1- is bonded to three Li1+ and one Mn3+ atom to form distorted edge-sharing FLi3Mn tetrahedra. In the fourteenth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Mn3+ atom. In the fifteenth F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Mn3+ atom.