Li6CuF8 crystallizes in the cubic Fm-3m space group. Li(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form LiF6 octahedra that share corners with six equivalent Li(1)F6 octahedra, edges with two equivalent Cu(1)F6 octahedra, and edges with eight equivalent Li(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Cu(1) is bonded to six equivalent F(2) atoms to form CuF6 octahedra that share edges with twelve equivalent Li(1)F6 octahedra. There are two inequivalent F sites. In the first F site, F(1) is bonded to six equivalent Li(1) atoms to form FLi6 octahedra that share corners with six equivalent F(1)Li6 octahedra and edges with twelve equivalent F(2)Li4Cu square pyramids. The corner-sharing octahedra are not tilted. In the second F site, F(2) is bonded to four equivalent Li(1) and one Cu(1) atom to form FLi4Cu square pyramids that share corners with nine equivalent F(2)Li4Cu square pyramids, edges with four equivalent F(1)Li6 octahedra, and edges with four equivalent F(2)Li4Cu square pyramids.
Li6CuF8 crystallizes in the cubic Fm-3m space group. Li(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form LiF6 octahedra that share corners with six equivalent Li(1)F6 octahedra, edges with two equivalent Cu(1)F6 octahedra, and edges with eight equivalent Li(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Both Li(1)-F(1) bond lengths are 2.07 Å. All Li(1)-F(2) bond lengths are 2.07 Å. Cu(1) is bonded to six equivalent F(2) atoms to form CuF6 octahedra that share edges with twelve equivalent Li(1)F6 octahedra. All Cu(1)-F(2) bond lengths are 2.02 Å. There are two inequivalent F sites. In the first F site, F(1) is bonded to six equivalent Li(1) atoms to form FLi6 octahedra that share corners with six equivalent F(1)Li6 octahedra and edges with twelve equivalent F(2)Li4Cu square pyramids. The corner-sharing octahedra are not tilted. In the second F site, F(2) is bonded to four equivalent Li(1) and one Cu(1) atom to form FLi4Cu square pyramids that share corners with nine equivalent F(2)Li4Cu square pyramids, edges with four equivalent F(1)Li6 octahedra, and edges with four equivalent F(2)Li4Cu square pyramids.