DOE OSTI2020
LiMn2F5 crystallizes in the monoclinic C2/c 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 tetrahedra that share corners with six MnF6 octahedra and an edgeedge with one MnF6 octahedra. The corner-sharing octahedra tilt angles range from 29–67°. There are a spread of Li–F bond distances ranging from 1.89–1.99 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with eight MnF6 octahedra. The corner-sharing octahedra tilt angles range from 39–65°. There is two shorter (1.91 Å) and two longer (1.95 Å) Li–F bond length. There are three inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to six F1- atoms to form distorted MnF6 octahedra that share corners with two MnF6 octahedra, corners with two LiF4 tetrahedra, edges with four MnF6 octahedra, and an edgeedge with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 29–31°. There are a spread of Mn–F bond distances ranging from 2.09–2.35 Å. In the second Mn2+ site, Mn2+ is bonded to six F1- atoms to form distorted MnF6 octahedra that share corners with two MnF6 octahedra, corners with four LiF4 tetrahedra, and edges with four MnF6 octahedra. The corner-sharing octahedra tilt angles range from 29–41°. There are a spread of Mn–F bond distances ranging from 2.08–2.35 Å. In the third Mn2+ site, Mn2+ is bonded to six F1- atoms to form distorted MnF6 octahedra that share corners with two MnF6 octahedra, corners with four LiF4 tetrahedra, and edges with four MnF6 octahedra. The corner-sharing octahedra tilt angles range from 31–57°. There are a spread of Mn–F bond distances ranging from 2.08–2.35 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted T-shaped geometry to one Li1+ and two Mn2+ atoms. In the second F1- site, F1- is bonded in a distorted T-shaped geometry to one Li1+ and two Mn2+ atoms. In the third F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Mn2+ atoms. In the fourth F1- site, F1- is bonded to four Mn2+ atoms to form distorted edge-sharing FMn4 trigonal pyramids. In the fifth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Mn2+ atoms. In the sixth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Mn2+ atoms. In the seventh F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two equivalent Mn2+ atoms. In the eighth F1- site, F1- is bonded to four Mn2+ atoms to form distorted edge-sharing FMn4 tetrahedra.