DOE OSTI2020
Li2AgF4 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Li–F bond distances ranging from 1.97–2.77 Å. In the second 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 1.97–2.29 Å. In the third Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share a cornercorner with one AgF6 octahedra, corners with two equivalent LiF4 tetrahedra, and a cornercorner with one LiF5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 73°. There are a spread of Li–F bond distances ranging from 1.90–2.03 Å. In the fourth Li1+ site, Li1+ is bonded to five F1- atoms to form LiF5 trigonal bipyramids that share corners with two equivalent AgF6 octahedra and a cornercorner with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–74°. There are a spread of Li–F bond distances ranging from 1.91–2.19 Å. In the fifth 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 1.93–2.50 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 1.92–2.24 Å. There are three inequivalent Ag2+ sites. In the first Ag2+ site, Ag2+ is bonded to six F1- atoms to form AgF6 octahedra that share corners with two equivalent AgF6 octahedra, a cornercorner with one LiF4 tetrahedra, and corners with two equivalent LiF5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 38°. There are a spread of Ag–F bond distances ranging from 2.09–2.55 Å. In the second Ag2+ site, Ag2+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Ag–F bond distances ranging from 2.13–2.15 Å. In the third Ag2+ site, Ag2+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.09–2.60 Å. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded to three Li1+ and one Ag2+ atom to form a mixture of distorted edge and corner-sharing FLi3Ag trigonal pyramids. In the second F1- site, F1- is bonded to three Li1+ and one Ag2+ atom to form a mixture of edge and corner-sharing FLi3Ag tetrahedra. In the third F1- site, F1- is bonded to three Li1+ and one Ag2+ atom to form a mixture of distorted edge and corner-sharing FLi3Ag trigonal pyramids. In the fourth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag2+ atoms. In the fifth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ atoms. In the sixth F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two Ag2+ atoms. In the seventh F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Ag2+ atoms. In the eighth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and two equivalent Ag2+ atoms. In the ninth F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two Ag2+ atoms. In the tenth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Ag2+ atom. In the eleventh F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag2+ atom. In the twelfth F1- site, F1- is bonded to three Li1+ and one Ag2+ atom to form corner-sharing FLi3Ag tetrahedra.