LiFeF3 crystallizes in the trigonal R-3c space group. Li(1) is bonded to one F(3), two equivalent F(1), and two equivalent F(2) atoms to form LiF5 trigonal bipyramids that share corners with two equivalent Fe(1)F6 octahedra, corners with two equivalent Fe(2)F7 pentagonal bipyramids, corners with six equivalent Li(1)F5 trigonal bipyramids, and edges with two equivalent Fe(2)F7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent F(1) atoms to form distorted FeF6 octahedra that share corners with six equivalent Li(1)F5 trigonal bipyramids and edges with six equivalent Fe(2)F7 pentagonal bipyramids. In the second Fe site, Fe(2) is bonded to one F(2) and six equivalent F(1) atoms to form distorted FeF7 pentagonal bipyramids that share corners with three equivalent Li(1)F5 trigonal bipyramids, edges with three equivalent Fe(1)F6 octahedra, edges with three equivalent Fe(2)F7 pentagonal bipyramids, and edges with three equivalent Li(1)F5 trigonal bipyramids. There are three inequivalent F sites. In the first F site, F(1) is bonded to one Li(1), one Fe(1), and two equivalent Fe(2) atoms to form FLiFe3 tetrahedra that share corners with two equivalent F(2)Li3Fe tetrahedra, corners with ten equivalent F(1)LiFe3 tetrahedra,  an edgeedge with one F(2)Li3Fe tetrahedra, and edges with three equivalent F(1)LiFe3 tetrahedra. In the second F site, F(2) is bonded to three equivalent Li(1) and one Fe(2) atom to form distorted FLi3Fe tetrahedra that share corners with three equivalent F(2)Li3Fe tetrahedra, corners with six equivalent F(1)LiFe3 tetrahedra, and edges with three equivalent F(1)LiFe3 tetrahedra. In the third F site, F(3) is bonded in a trigonal planar geometry to three equivalent Li(1) atoms.
LiFeF3 crystallizes in the trigonal R-3c space group. Li(1) is bonded to one F(3), two equivalent F(1), and two equivalent F(2) atoms to form LiF5 trigonal bipyramids that share corners with two equivalent Fe(1)F6 octahedra, corners with two equivalent Fe(2)F7 pentagonal bipyramids, corners with six equivalent Li(1)F5 trigonal bipyramids, and edges with two equivalent Fe(2)F7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 64°. The Li(1)-F(3) bond length is 1.85 Å. Both Li(1)-F(1) bond lengths are 2.11 Å. Both Li(1)-F(2) bond lengths are 2.03 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent F(1) atoms to form distorted FeF6 octahedra that share corners with six equivalent Li(1)F5 trigonal bipyramids and edges with six equivalent Fe(2)F7 pentagonal bipyramids. All Fe(1)-F(1) bond lengths are 2.09 Å. In the second Fe site, Fe(2) is bonded to one F(2) and six equivalent F(1) atoms to form distorted FeF7 pentagonal bipyramids that share corners with three equivalent Li(1)F5 trigonal bipyramids, edges with three equivalent Fe(1)F6 octahedra, edges with three equivalent Fe(2)F7 pentagonal bipyramids, and edges with three equivalent Li(1)F5 trigonal bipyramids. The Fe(2)-F(2) bond length is 2.18 Å. There are three shorter (2.16 Å) and three longer (2.21 Å) Fe(2)-F(1) bond lengths. There are three inequivalent F sites. In the first F site, F(1) is bonded to one Li(1), one Fe(1), and two equivalent Fe(2) atoms to form FLiFe3 tetrahedra that share corners with two equivalent F(2)Li3Fe tetrahedra, corners with ten equivalent F(1)LiFe3 tetrahedra,  an edgeedge with one F(2)Li3Fe tetrahedra, and edges with three equivalent F(1)LiFe3 tetrahedra. In the second F site, F(2) is bonded to three equivalent Li(1) and one Fe(2) atom to form distorted FLi3Fe tetrahedra that share corners with three equivalent F(2)Li3Fe tetrahedra, corners with six equivalent F(1)LiFe3 tetrahedra, and edges with three equivalent F(1)LiFe3 tetrahedra. In the third F site, F(3) is bonded in a trigonal planar geometry to three equivalent Li(1) atoms.