LiFeF3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(3), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Fe(1)F6 octahedra, corners with three equivalent Fe(2)F6 octahedra, corners with two equivalent Li(1)F4 tetrahedra, and  an edgeedge with one Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 23-64°. In the second Li site, Li(2) is bonded to one F(4), one F(5), and two equivalent F(6) atoms to form LiF4 tetrahedra that share corners with three equivalent Fe(2)F6 octahedra, corners with four equivalent Fe(1)F6 octahedra, and corners with two equivalent Li(2)F4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-70°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one F(1), one F(2), one F(3), one F(4), one F(5), and one F(6) atom to form distorted FeF6 octahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with four equivalent Li(2)F4 tetrahedra, edges with three equivalent Fe(2)F6 octahedra, and  an edgeedge with one Li(1)F4 tetrahedra. In the second Fe site, Fe(2) is bonded to one F(2), one F(4), two equivalent F(3), and two equivalent F(5) atoms to form FeF6 octahedra that share corners with three equivalent Li(1)F4 tetrahedra, corners with three equivalent Li(2)F4 tetrahedra, edges with two equivalent Fe(2)F6 octahedra, and edges with three equivalent Fe(1)F6 octahedra. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one Fe(1) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Li(1), one Fe(1), and one Fe(2) atom. In the third F site, F(3) is bonded to one Li(1), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted edge and corner-sharing FLiFe3 tetrahedra. In the fourth F site, F(4) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Fe(2) atom. In the fifth F site, F(5) is bonded to one Li(2), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted edge and corner-sharing FLiFe3 tetrahedra. In the sixth F site, F(6) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Fe(1) atom.
LiFeF3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(3), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Fe(1)F6 octahedra, corners with three equivalent Fe(2)F6 octahedra, corners with two equivalent Li(1)F4 tetrahedra, and  an edgeedge with one Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 23-64°. The Li(1)-F(2) bond length is 1.91 Å. The Li(1)-F(3) bond length is 1.94 Å. There is one shorter (1.85 Å) and one longer (1.90 Å) Li(1)-F(1) bond length. In the second Li site, Li(2) is bonded to one F(4), one F(5), and two equivalent F(6) atoms to form LiF4 tetrahedra that share corners with three equivalent Fe(2)F6 octahedra, corners with four equivalent Fe(1)F6 octahedra, and corners with two equivalent Li(2)F4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-70°. The Li(2)-F(4) bond length is 1.89 Å. The Li(2)-F(5) bond length is 1.98 Å. Both Li(2)-F(6) bond lengths are 1.89 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one F(1), one F(2), one F(3), one F(4), one F(5), and one F(6) atom to form distorted FeF6 octahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with four equivalent Li(2)F4 tetrahedra, edges with three equivalent Fe(2)F6 octahedra, and  an edgeedge with one Li(1)F4 tetrahedra. The Fe(1)-F(1) bond length is 2.00 Å. The Fe(1)-F(2) bond length is 2.19 Å. The Fe(1)-F(3) bond length is 2.23 Å. The Fe(1)-F(4) bond length is 2.08 Å. The Fe(1)-F(5) bond length is 2.26 Å. The Fe(1)-F(6) bond length is 2.03 Å. In the second Fe site, Fe(2) is bonded to one F(2), one F(4), two equivalent F(3), and two equivalent F(5) atoms to form FeF6 octahedra that share corners with three equivalent Li(1)F4 tetrahedra, corners with three equivalent Li(2)F4 tetrahedra, edges with two equivalent Fe(2)F6 octahedra, and edges with three equivalent Fe(1)F6 octahedra. The Fe(2)-F(2) bond length is 1.98 Å. The Fe(2)-F(4) bond length is 2.08 Å. There is one shorter (2.16 Å) and one longer (2.20 Å) Fe(2)-F(3) bond length. There is one shorter (2.08 Å) and one longer (2.24 Å) Fe(2)-F(5) bond length. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to two equivalent Li(1) and one Fe(1) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Li(1), one Fe(1), and one Fe(2) atom. In the third F site, F(3) is bonded to one Li(1), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted edge and corner-sharing FLiFe3 tetrahedra. In the fourth F site, F(4) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Fe(2) atom. In the fifth F site, F(5) is bonded to one Li(2), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted edge and corner-sharing FLiFe3 tetrahedra. In the sixth F site, F(6) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Fe(1) atom.